Alignment device for a tibial resection guide

ABSTRACT

An alignment device for a tibial resection guide includes a clamping device having at least two clamping elements acting against one another for clamping the distal end of a tibia of a patient. A contact device for contacting the proximal end of the tibia includes a tool guiding device for guiding a tool during the resection of the tibia. A telescopic device is separably connected to the contact device and adjustably connected to the clamping device. The telescopic device is designed to align the contact device and clamping device with respect to the tibia. The telescopic device has a decoupling device configured to separate the contact device from the telescopic device when activated. The clamping elements are designed such that the telescopic device can be removed from the tibia with one hand after the decoupling device is activated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Stage Entry of InternationalApplication No. PCT/EP2021/059647, filed Apr. 14, 2021, and claimspriority to German Application No. 10 2020 110 346.8, filed Apr. 15,2020. The contents of International Application No. PCT/EP2021/059647and German Application No. 10 2020 110 346.8 are incorporated byreference herein in their entireties.

FIELD

The present disclosure relates to an alignment device or alignment aidfor a tibial resection guide comprising a clamping device which has atleast two clamping elements acting against one another for clamping thedistal end of a tibia of a patient; which comprises a contact device forcontacting the proximal end of the tibia, which device comprises a toolguiding device for guiding a tool during the resection of the tibia; anda telescopic device which is separably connected to the contact deviceand adjustably connected to the clamping device and is designed to alignthe devices with respect to the tibia.

BACKGROUND

The precise resection of a patient’s bone, especially the tibia, is ofgreat importance for the success of an operation to implant a jointprosthesis. The plane of the resection must be precisely localized inorder to minimize a degree of bone removal on the one hand, while at thesame time it has to be ensured that all of the defective bone tissue isremoved as well. The alignment of the plane in relation to an anatomicalaxis, in particular a tibial axis, must be continuously monitored duringsurgery to ensure the alignment of the joint surfaces of the joint overthe entire region of joint motion.

The exact definition of a tibial resection plane in a knee joint isusually set using an alignment device or adjustment guide (for a sawblock) with a columnar adjustment rod or telescopic device attachedremote from the tibia near the ankle. The telescopic device extendsalong the tibia (essentially) parallel to the corresponding anatomicaltibial axis. The resection plane can then be defined in relation to thetibial axis. Finally, a tool guiding device attached to the alignmentdevice defines the plane of resection. Usually, the tool guiding devicehas a passage slot for this purpose, through which a planar cuttingedge, pivoting back and forth, of a surgical instrument (saw) is passed.

In order to adjust the alignment of the tibia resection plane, analignment device is attached to the tibia, which is connected to thetelescopic device at its one end pointing towards a foot of the patient,and the tool guiding device is connected to its other end (end portion).Here, a basic distinction is made between two alignment and fixationprinciples, namely “anterior fixation” and “proximal fixation”. In thecase of “anterior fixation”, the alignment device is fastenedexclusively by means of the foot/ankle shackle described above, whereasin the case of “proximal fixation”, additional drive pins are providedat the proximal end portion of the alignment device, which are driven inat the so-called Eminentia intercondylaris tibiae.

US 6,221,035 B1 discloses an ankle/bone shackle in the form of afixation clamp of an alignment aid of the anterior fixation type used intibial resection. In this case, the fixation clamp is located at thedistal end portion of a telescopic alignment rod, to the distal endportion of which a tibia cut block is mounted.

The clamp itself has two spring-biased clamping arms, each of which canbe rotated about an axis of rotation relative to a frame. These clampingarms are brought into an open position and, after contact with thetibia, are released hereafter by means of a manual release device. Dueto the spring preload, they then enclose an ankle joint or the tibia andclamp it. The clamping arms are pretensioned in the closing/clampingdirection. The spring preload causes a force-fit fixation of thealignment aid at or immediately above the ankle, which has thedisadvantage, however, that hematomas can occur on the patient at theaffected body parts due to the clamping force.

The clamping arms exert a spring-loading effect on the ankle joint orankle. However, the fixation clamp is not adapted to a patient’sanatomy, so that the clamping arms exert a different degree of contactforce/clamping force depending on the foot/leg shape and the thicknessof the ankle joint. This also results in a holding force of the fixationclamp that depends on the shape of the ankle.

Furthermore, a tibia alignment guide of the proximal fixation type isknown, for example, from US 7 344 542 B2, in which a transverse beam isrigidly connected to a telescope-type main rod at its proximal endportion. At the free end portion of the transverse beam, fastening pinsare mounted which are driven into the tibia for additional fixation ofthe alignment aid; moreover, a lever is also supported on the transversebeam which, when actuated, presses against the tibia to pull the pinsheld on the transverse beam out of the tibia. This means that the entiretransverse beam together with the integrated pins is levered out againstthe bone, as a result of which the connection between the tibia cutblock or saw gauge and the vertical main rod must be simultaneouslyreleased in a disadvantageous manner.

Finally, a surgical nail puller is known in principle from US2010/0087831 A1, which can reach under a nail head and pull it out ofthe bone by means of a lever and a transmission.

Tibia alignment aids/alignment devices of the type described above havefundamental problems, particularly with regard to their handling:

-   For example, it is necessary to have available alignment aids of    different design for the two attachment principles mentioned. This    is expensive and complicates the entire handling process including    storage, sterilization, etc.-   Furthermore, the alignment aid is often removed from a patient’s leg    during a surgical procedure. This always requires several manual    operations/actions with conventional alignment aids, depending on    the fastening principle, for example to loosen the distal and/or    proximal fastenings.-   At this point, it should be noted once again that body dimensions    are patient-specific and vary considerably. The conventional    alignment aids of known design, however, can only cover a limited    range of deviation in each case by means of corresponding adjustment    options. This means that with the known systems it is not possible    to cover the complete, worldwide length spectrum of tibiae in each    case, but several systems/alignment aids with possibly overlapping    length spectra must be kept in stock, which entails the problems    already mentioned above with regard to costs and complicated    handling processes. Also, for the adjustment of the varus/valgus    alignment, the length of the telescopic rod/main rod that is    coarsely adjusted first must always be actively (manually) secured    against misalignment. This means that a subsequent fine correction    of the length adjustment always requires a manipulation (e.g.    temporary manual partial release) of a locking mechanism, which is    normally supposed to fix the roughly adjusted length.-   Another problem of the prior art is that the fixation to the    patient’s ankle is usually made in a force-fitting manner or the    clamping arms are preloaded in a force-fitting manner, causing an    insufficient ability of positioning due to the resulting inherent    elasticity of the clamping arms. There is no adaptation to the    patient’s anatomy. In the worst case, this leads to a detachable    fixation, which, however, is not sufficient due to the high    requirements for dimensional accuracy or precision on the alignment    of the plane of the resection described at the beginning. Also, the    different clamping forces of the elastically pretensioned clamping    arms can cause, among other things, hematomas on the patient’s body    parts.-   Not all anatomical sizes are covered by the fixation clamps known in    the prior art, since the clamping force depends on the respective    anatomy of the patient. Therefore, different variants of fixation    clamps of the alignment device would have to be manufactured and    kept ready for an optimum adaptation, but this is not practiced in    practice due to high costs and poor manageability. In the case of    alignment device fixation clamps, which are spring-loaded against    the ankle, there is the problem that, depending on the shape of the    foot and the thickness of the ankle, the contact force exerted by    the spring varies.

SUMMARY

It is therefore a fundamental object of the present invention to atleast partially avoid or at least reduce the above-mentioneddisadvantages of the prior art and, in particular, to provide a (tibia)alignment device which allows efficient handling, in particular asimple, safe and fast fixation as well as simple and fast release of thefixation from a body extremity/body limb/lower leg of a patient, thealignment device being preferably adapted or adaptable for differentanatomies of body extremities and being preferably usable for anyanatomy and avoiding hematomas as far as possible by its modes ofoperation and configurations. Also, the alignment device shouldpreferably have a design that is as simple as possible and, ifnecessary, easy to assemble, clean and sterilize. On the whole, itshould also be possible to keep the costs associated with the handlingof an alignment device or alignment aid of the type in question as lowas possible. Finally, the alignment device should preferably be asflexible as possible in terms of applications.

The alignment device (“extramedullary tibia alignment system”) accordingto the present invention is/forms an extramedullary alignment system, inparticular for performing the proximal tibial incision in a total orunicondylar knee arthroplasty (TKA/UKA) according to the rules. It canessentially be used to adjust the saw block, known from the prior art,for the proximal tibial incision to the appropriate landmarks of thetibia according to clinical requirements and the surgeon’s conception,and to achieve sufficient stability when attaching the saw block to theanterior epiphyseal region of the tibial bone. Furthermore, if desiredby the surgeon, it should ensure a sufficiently high stability alsoduring sawing the bone with the help of the saw block, for example bykeeping the alignment device selectively fixed to the tibia.

The present system or the alignment device according to the inventionfulfills both different alignment and fixation principles required bythe users in one unit. In the following, these are the versions referredto as “anterior fixation” and “proximal fixation”. The designation wasmade according to their primary fixation option as already definedabove. According to the invention, the version “proximal fixation” ispreferably achieved by placing an additional “proximal fixation unit”(adapter-like) on the version “anterior fixation”, thus additionallyallowing the proximal fixation to the “Eminentia intercondylaristibiae”. In the case of the “anterior fixation”, the primary fixation(as standard) is performed in the proximal region by means of a pinplaced in the “Tuberositas tibiae” through an oblong hole in the sawblock.

The following parameters are set or aligned with the alignment deviceaccording to the invention:

-   The varus/valgus-cutting angle.-   The flexion/extension-cutting angle (posterior/anterior or also    dorsal/ventral cutting angle (slope)).-   The proximal cutting height (≙ thickness of the desired bone    section).

The alignment device according to the invention consists essentially ofthe following components:

-   Distal retaining clamp, especially foot clamp    -   The distal retaining clamp (hereinafter referred to only by way        of example as a foot clamp) is located at the distal end of the        alignment device according to the invention. It fulfills the        following functions:        -   Holding and stabilizing the alignment device in the region            of the ankle with regard to lateral and rotational movements            relative to the tibia (or relative to the anatomical tibial            axis and thus usually also relative to the mechanical tibial            axis)        -   Alignment of the alignment device in reference to the distal            landmarks            -   1. distal anterior ankle center            -   2. distal tibial anterior edge        -   Adjustability of the following parameters:            -   1. varus/valgus cutting angle            -   2. anterior/posterior cutting angle (slope)        -   Easy and traumatic removal of the alignment device from the            patient’s leg        -   Enlargement/reduction of the longitudinal range of the            alignment device-   Shaft    -   The (telescopic) shaft is preferably made up of a slide rod and        a handle. These two elements are connected to each other like in        a telescope. The shaft connects the distal instrument part (foot        clamp) with the proximal instrument part (saw block, if        necessary an adapter for the saw block and/or an attachment arm        for the version with proximal attachment).        -   The shaft also fulfills the following additional functions:            -   It supports the alignment of the alignment device with                regard to all three parameters mentioned above. This is                done by referencing the shaft visually and/or haptically                by simultaneously contacting the tibial leading edge                (with index finger, middle finger and thumb) and the                anterior shaft edge (with the base of the hand between                index finger and thumb) to the tibial leading edge.            -   It preferably includes an arresting unit (hand screw                with spring-loaded clamping element, for instance) that                is used to secure the set alignment height for the                alignment device. In the version “anterior fixation”,                the height adjustment of the alignment device is set                exclusively via this function. For the version “proximal                fixation”, there is preferably also an adaptively                attachable, vertically shiftable carriage to which the                saw block is then attached or attachable.            -   Another function of the arresting unit is to secure the                initially estimated and not yet finally determined                height setting when aligning the alignment device. This                is done by means of a self-locking effect, for example                realized with a spring-loaded pin in the arresting unit,                which presses against the distal shaft portion of the                alignment device. This allows the user to make                corrections regarding the alignment of varus/valgus,                rotation and height at the same time. The adjustable                self-adhesion prevents the alignment device from                collapsing due to gravity and thus facilitates handling                and expenditure of time, thus having a positive effect                on operating time and thus on the surgical team and                patients.        -   The clamping unit can be realized in different versions.            -   1. By a solution with clamping function and                self-adhesive sliding function or            -   2. With clamping function, self-adhesive sliding                function and fully opened with free-falling function.-   Adapter for fastening the saw block to the shaft    -   A preferably provided saw block adapter is located at the        proximal end of the alignment device (especially at the handle)        and has the following functions.        -   Accommodating the tibia saw blocks for the right or left            leg.        -   Free gliding arrangement on the shaft, especially in            combination with the version “proximal fixation” for the            final cutting height adjustment. The use of free gliding is            also conceivable with the version “anterior fixation”,            especially if the adapter is initially fixed in a central            position. This allows easier height correction after            arresting the fixation unit.-   Proximal fixation unit    -   An optionally arranged “proximal fixation unit” essentially        consists of a horizontal cantilever arm and a vertical support        column. The “proximal fixation unit”, or vertical support        column, can be selectively attached to the proximal end of the        shaft in the version “anterior fixation”. It has the following        functions:        -   Easy fixation and release of the “proximal fixation unit” in            the proximal shaft part in the version “anterior fixation”        -   Horizontal movability of the cantilever arm in the support            column, if necessary with self-adhesion, if no to low            sliding forces act from outside. The movability of the            cantilever arm guarantees that the alignment device is            compatible with tibial anatomies worldwide and that the user            can set the intended slope at any time.        -   Securing against rotation and lateral displacement by            fixation to the Eminentia intercondylaris tibiae by means of            preferably two drive pins.        -   Releasing the pins with the impact lever.        -   Guiding the saw block adapter during cutting height            adjustment.-   Adjustable cutting height feeler    -   The cutting height feeler can be selectively attached to the        proximal tibia saw block and essentially consists of the        following elements:        -   Adapter interface to the tibia saw block with            lock-and-release mechanism        -   Self-retaining, sliding contact arm with contact tip        -   Unit for height adjustment    -   The adjustable cutting height feeler has the following        functions:        -   Easy assembly and disassembly of the cutting height feeler            to the tibia saw block(s).        -   Scanning of a bony landmark with the contact tip. The            landmark selected by the user is the reference relative to            which the cutting height is set.        -   Horizontal movability of the height feeler to adapt to the            different anatomies of the epiphyseal tibia and to reach the            medial and lateral tibial condyle from the same adapter            site.        -   Adjustment of the cutting height-   Proximal tibia saw block    -   There are preferably different variants of tibia saw blocks. The        variants differ in the following features:        -   Applicable for the right and left tibia        -   Adapted to the two versions “anterior fixation” and            “proximal fixation”.    -   The saw blocks have the following function or functional        elements:        -   Guidance of the saw blade for the bone section        -   Holes for attaching the saw block to the bone and for            correcting the cutting height up to ±4 mm        -   Adapter interface for mounting on the alignment device/shaft            via the (saw block) adapter        -   Adapter interface for mounting the cutting height feeler    -   The above objects of the invention are described in more detail        below:        -   A first gist of the present invention includes, inter alia,            providing an alignment device, in particular for a tibial            resection guide, with a telescopically extendable shaft            (telescopic device), which can be equipped/is equipped with            a saw block at its proximal end region and has a type of            (foot) shackle device, in particular a clamping device, at            its distal end region, which comprises at least two pivoting            clamping elements/clamping arms acting against one another            for clamping the distal end of, for example, a tibia of a            patient, the clamping elements of the clamping device being            each of arcuate design and aligned with one another in such            a way that, viewed in the direction of the longitudinal axis            of the alignment device/shaft, they form between them an            oval-shaped region which is designed for receiving the            distal region of the tibia in a clamping manner. According            to the invention, the clamping elements are each designed to            be resilient or are made of a resilient material, so that            the clamping device of the alignment device can be removed            from the tibia preferably with one hand by utilizing the            spring properties of the clamping elements.

In other words, the clamping device arranged at the distal end portionof the alignment device or of the telescopic/extendable shaft has apreferably Y-shaped tibia contact block consisting, among other things,of two essentially V-shaped diverging, rigid contact arms (forming acarriage), to the respective free end regions of which the resilientlybendable/yielding clamping arms are pivotably articulated, which in turnare each preformed in an arc shape in the closing-pivotingdirection/clamping direction. If the clamping arms formed in this wayare pivoted towards each other in clamping direction (foot clampclosed), the above-mentioned oval clamping shape results in top view, asa result of which a tibia clamped by it in the ankle region of a patientis simultaneously subjected to force almost along the entirecircumference of the clamp, in particular from behind, laterally andfrom the front.

Due to the resilient design of the clamping elements, they are alsoattached to the distal end of the tibia in a way that is gentle on thetissue, i.e. atraumatic, with high translational and rotationalstability. When reference is made to the lower end of the tibia, thisrefers to the region of the lower tibial third including the ankle jointdirectly up to the contact of the dorsum of the foot.

The alignment device or the ankle shackle device (foot clamp) furtherpreferably comprises a ratchet mechanism via which the clamping elementsare each supported on the tibia contact block of the ankle shackledevice and by means of which the clamping elements can be pretensionedindependently of one another with different pretensioning forces.

Due to the spring elasticity, the clamping elements advantageously haveelasticity and at the same time a high holding force and high rotationaland translational stability against unintentional adjustment of theentire alignment device. This high stability is achieved by the factthat the clamping elements are closed and additionally held by theratchet mechanism.

Furthermore, the two clamping elements interlace at their respectivefree ends when the foot clamp is closed. Due to this interlacing, it isadvantageously possible to simultaneously apply a lateral holding forceand a holding force coming from lateral posterior direction. In thisway, a high areal closing and holding force is appliedmultidimensionally to the tibia in an advantageous manner.

In a particularly advantageous manner, this holding force is constantfor all anatomical circumferential sizes of the tibia, since theresilient clamping elements are only stressed when they come intocontact with the tibia. The clamping elements thus advantageouslyfulfill a dual function, as the compressive force to hold the tibia isonly applied when the tibia contacts the clamping elements.

According to a further preferred embodiment, the clamping elements areadditionally each fork-shaped in design and the prongs of the respectivefork are arranged offset from one another in such a way that, in theclosed state (closed foot clamp), they engage one another in overlappingmanner so that the tibia is held firmly. The clamping elements thuseffect simultaneous gripping and holding of the tibia from behind,laterally and from the front. Configuring the clamping elements in afork shape allows them to interlace in the posterior region of the tibiaand thus press the latter against the contact block. In a particularlyadvantageous manner, the clamping elements are designed in such a waythat they interlace in the region of the ankle joint.

Preferably, the respective tips of the prongs are shaped opposite to therespective arc shape of the clamping elements, so that the removalprocess from the tibia occurs without any injury. The fact that theclamping elements are curved in their end region means that they can bepulled off the tibia in a very tissue-friendly manner (without firsthaving to open the ratchet mechanism), while it is advantageouslyprevented or reduced that the ends cut into the tissue.

A second gist of the present invention is that the telescopic device,i.e. the telescopic shaft in its proximal region, preferably in additionto the foot clamp described above, comprises a decoupling device, i.e. asaw block adapter (may also be referred to as a decoupling device),which is designed to separate/uncouple the saw block from the telescopicdevice or the shaft upon (manual) activation/release. In this way, it iseasily possible to disconnect the alignment device/alignment aid, i.e.the telescopic shaft, from the cutting/saw block with virtually onemanual operation. In a preferred case, if the foot clamp is designedaccording to the first main idea of the present invention describedabove, the clamping elements can be easily pulled off the distal tibia(also with one hand) due to their inherent elasticity under resilientspreading (and without opening the foot clamp at the ratchet mechanism),so that the alignment device as a whole can be removed with a singlemovement.

In other words, advantageously, due to the constructional design of thefoot clamp and the proximal saw block adapter/adapter interface, thetelescopic shaft (or the alignment aid) can be pulled off the patient’stibia in a tissue-gentle manner, i.e. in a non-traumatic manner, and inone simple (single) operating action.

The decisive factor here is that the retaining elements of the footclamp are designed to be sufficiently elastic so that they can be easilyremoved from the distal tibia without the need to operate a releasemechanism, and that at the same time they exhibit sufficiently highrotational and translational stability against unintentional adjustmentof the alignment device. In addition, it is advantageous for this casethat the decoupling device, i.e. the adapter interface, for the tibiasaw block is designed in such a way that the handle for releasing(preferably a lever or release button) the alignment device from the sawblock can be actuated with a simple thumb pressure so that the shaft canbe grasped by the associated whole hand. With the alignment devicecomprising the described devices and elements, it is thus possible,after attachment of the saw block to the bone and after operating therelease button by thumb pressure, to remove the alignment device fromthe patient’s tibia with one hand without the need for any furtheroperating action.

According to a preferred embodiment to the second main idea of thepresent invention, the telescopic device and/or the telescopic shaft hasin its proximal region a handle which is designed in such a way that itcan be grasped by one hand and that the decoupling device/saw blockadapter for activation has a pressure element above the handle, whichpressure element is preferably arranged at an angle A of between 90° and150°, more preferably at an angle of between 95° and 120° and inparticular at an angle A of 100° to the longitudinal axis of thetelescopic device, so that the pressure element can be activated by thethumb of the one hand.

The arrangement of the pressure element at the preferred angle A of 100°creates a position of the pressure element that is particularly easy toreach. Thus, the pressure element can be advantageously triggered with asingle thumb pressure and the alignment device can be removed from thetibia by a single hand of the operator. Advantageously, this preventsadditional hand movements or procedural steps, making the alignmentdevice removable in a single motion.

More specifically, the saw block adapter is designed on the side of theshaft as a male adapter interface approximately in the manner of a plug,for example with two peg-shaped protrusions, on which a clamp orretaining bracket is preferably mounted in a rocker-like manner. Theretaining bracket forms at least one engagement undercut (e.g. latchinghook) at its one end portion, whereas the pressure element for manualpivoting of the retaining bracket preferably in the release direction isarranged at its other end portion.

Accordingly, a female adapter interface, such as in the manner of asocket with e.g. two (blind) bores, is arranged/designed on the sawblock, which can be engaged by the plug in particular in a torque-proofmanner, this engagement being secured by means of the retaining bracket,for example by engaging behind retaining edges on the side of the sawblock. It should be expressly noted at this point that the male adapterinterface can of course also be provided on the side of the saw blockand the female adapter interface on the shaft.

Preferably, the saw block adapter is formed as a separate (independent)component comprising a docking point to which the adapter can be firmlyconnected with handle preferably at its proximal end. Further preferred,the saw block adapter has a vertical through hole such that the one partof the telescopic shaft (slide rod element, on which the foot clamp isdistally arranged) can slidingly (completely) penetrate both the handleand the adapter.

Further, according to a third inventive main idea, the present inventionconsists in providing an alignment device for a tibial resection guide,comprising the following components:

-   a clamping device (foot clamp) for clamping the distal end of a    tibia of a patient preferably according to the first main idea of    the invention;-   a tool guiding device/saw block for guiding a tool/saw during    resection of the tibia,-   a telescopic device/telescopic shaft preferably according to the    second main idea of the invention, which is connected to the tool    guiding device/saw block and to the clamping device and which is    designed to align the devices with respect to the tibia, the    telescopic device comprising a handle element or handle designed to    receive a slide rod element movably mounted therein (with clamping    device distally arranged thereon), the telescopic device comprising    a (manually adjustable) securing element which is arranged between    the handle and the slide rod element and which can be (manually)    adjusted to reach a first position in which a first compressive    force is brought about between the handle and the slide rod element,    and which can additionally be adjusted to reach a second position in    which a second compressive force is brought about between the    elements which differs from (is larger than) the first compressive    force.

Thus, a securing element is provided which is connected to thetelescopic device and which is designed to be arranged between thehandle and the slide rod element and which can generate a first and asecond compressive force between the handle and the slide rod element.By providing two different compressive forces between the elements, thetelescopic device is readily adjustable and operable depending on therequirements of the treating physician.

A preferred embodiment is provided in that, in the first position, the(first) compressive force generated thereby causes a self-locking effectbetween the handle element and the slide rod element in a verticalarrangement of the alignment device, i.e. in the longitudinal directionof the telescopic shaft, and in that, in the second position, the(second) compressive force generated thereby causes the elements to befixed relative to one another.

In the first position, therefore, a merely self-locking slide rod isadvantageously effected, the self-locking effect being at leastsufficient to prevent a relative displacement of handle and slide rodelement due to gravity, and in the second position a fixing of the sliderod in the handpiece is additionally effected by means of the securingelement. The fixation, for example by means of frictional clamping, isadvantageously achieved by screwing the securing element, i.e. anarresting/fastening screw, in as far as to the limit stop. Theself-locking release of the slide rod for its axial movability in thehandle is achieved by incorporating a spring-loaded pin in the securingelement, i.e. in the arresting/fastening screw, which generates africtional connection by means of a (spring-force-dependent) clampingforce between the handle and the slide rod when the screw is partiallyto fully open. This clamping force is designed such that the generatedstatic friction counteracts gravity, with the acting mass beingsignificantly influenced by the elements attached to the proximal and/ordistal end of the alignment device. Advantageously, the clamping forcehas the effect that the treating physician or user is able to releasethe elements for height adjustment at any time and the set height ismaintained. The alignment device thus advantageously does not collapse,as would be expected due to gravity. This allows the user to readjustthe height at any time while being able to concentrate on the adjustmentof the other parameters, e.g. varus/valgus and/or slope. On the whole,this facilitates the workflow during treatment in a beneficial way. Onlywhen the (rough) height adjustment has been completed, thearresting/fastening screw is screwed in as far as to the limit stop, asa result of which the spring effect is neutralized and a clamping forceis applied between the handle and the slide rod (element) as a functionof the screw-in force, which is much higher than the spring forcepreviously applied and ultimately clamps the two elements firmly againsteach other.

In a further preferred embodiment, the securing element is additionallyadjustable in such a way that in a third position a third compressiveforce acts between the elements, which is designed in such a way that ina vertical arrangement of the alignment device the elements (handle,slide rod) automatically slide into each other due to the appliedgravity. In this third position, a free-falling slide rod is thusprovided.

This is achieved, for example, by the fact that the clamping pin of thesecuring element no longer generates any static friction or only alow/negligible static friction, which in turn is caused by the fact that— when the fastening screw is fully opened — the force of the springacting on the clamping pin is so low that the static friction describedis no longer relevant and there is only a sliding friction between theclamping pin and the slide rod.

A further, fourth main idea of the present invention is to provide analignment device for a tibial resection guide comprising the followingcomponents:

-   a clamping device (ankle shackle) preferably according to the first    main idea of the invention for clamping the distal end of a tibia of    a patient;-   a tool guiding device/tibia saw block for guiding a tool during the    resection of the tibia,-   a telescopic device/telescopic shaft preferably according to the    second and/or third main idea of the invention, which is connected    or can be connected to the tool guiding device and to the clamping    device and which is designed to align the devices with respect to    the tibia, wherein the tool guiding device has a seating    recess/docking/adapter interface designed to releasably receive a    height sensing element or cutting height feeler (adjustable contact    element) for sensing/fine adjustment of the resection height.

According to the above embodiment, the cutting height feeler isselectively attached to the proximal tibia saw block and consistsessentially of the following elements:

-   An adapter interface to the tibia saw block preferably with latching    and releasing mechanism-   If necessary, a self-retaining but sliding contact arm with contact    tip-   A unit for (manual) height adjustment

The (adjustable) cutting height feeler has the following functions:

-   Simple assembly and disassembly of the stylus to the individual    tibia saw blocks, which may be designed so as to differ from each    other (e.g. for left and right leg)    -   If necessary, a spring-loaded latching mechanism is attached to        the distal end of the stylus, which arrests the stylus in place        after the stylus has been introduced/inserted into holes/seating        recesses/docking points provided for this purpose in the tibia        saw blocks. The stylus remains rotatable around the insertion        axis relative to the respective saw block.    -   The optional axial arresting is achieved, for example, via a        “spring-loaded nose” that is pushed back laterally during        insertion due to the beveled distal contact surface and locks in        place in a groove in the tibia saw block when fully inserted        into the tibia saw block.    -   The “spring-loaded nose” can be released from the arresting        position by means of a lever, which pulls the nose back against        the spring when operated, thus releasing the lock. In this        state, the stylus can be easily removed from the saw block.-   Scanning a bony landmark with the contact tip. The landmark selected    by the user is the reference against which the cutting height is    set.    -   The landmark is detected with the contact tip, which is attached        to the posterior end of the contact arm. Due to the fineness of        the contact tip, very small bony structures can be detected        visually very well and accurately by means of eye control.-   Horizontal movability of the height feeler to adapt to the different    anatomies of the epiphyseal tibia and to reach the medial and    lateral tibial condyle from the same adapter site.    -   With the help of the preferably rotatable stylus and the contact        arm which is preferably movable along its main axis, any bony        landmark on the proximal surface of the tibial condyles can be        reached. In this context, the dimensions of the contact arm are        designed such that the worldwide anatomy (of Asians, Caucasians,        etc.) is taken into account.    -   In order to maintain the desired extended length of the contact        arm, the contact arm can be secured against axial displacement,        e.g. in self-locking manner by means of a frictional engagement.-   Adjusting the cutting height    -   By latching the stylus in place in the tibia saw block and due        to a defined stop of the stylus on the saw block, the distance        of the contact tip of the stylus is determined in relation to        the lower edge of the saw slot in the saw block.    -   The set cutting height is indicated by numbers, for example, on        the circumference of a screw head of the adjustable height        feeler. The number indicating the set height is preferably        indicated by a pointing element at the anterior end of the        holding unit of the contact arm.    -   The adjustment of the tibial section thickness from 0 to 16 mm        (or 0 to 14 mm) is achieved with preferably only one turn of the        screw head. In this case, the height is adjusted by means of a        spiral in a guide element of the screw head. A stop element at        the upper end of the guide element can be provided, if        necessary, to prevent the screw head from being completely        unscrewed from the stylus.-   Final adjustment of the cutting height and alignment of the    alignment device for the proximal tibia cut:    -   After setting the desired cutting height, the stylus is moved        against the landmark selected by the user and the alignment        device is aligned. The landmark is approached by moving the        handle together with the mounting elements/saw block adapter on        the slide rod. Once the alignment device is aligned in height        and varus/valgus and slope are aligned as desired by the user,        the saw block is finally firmly anchored to the bone with a        fixation pin through the fixation holes provided for this        purpose in the saw block. After this, at least the stylus must        be removed in order to be able to perform the tibial saw cut.

The height sensing element, which is also referred to here as thecutting height feeler, can be attached to the proximal tibia saw block,as explained above. By using the height sensing element, the distance ofthe contact tip of the height sensing element relative to the lower edgeof a saw slot of the tool guiding device/saw block is defined in anadvantageous manner. The contact tip of the height sensing elementadvantageously allows very fine bony structures to be detected veryprecisely by means of eye control. On the whole, the height sensingelement achieves a particularly precise alignment of the entirealignment device.

In a preferred embodiment, the seating recess is a (blind or through)bore extending from the top side of the tool guiding device/saw blockalong the longitudinal axis of the alignment device/shaft, the heightsensing element having an insertion element/peg comprising a latchingmechanism, which can be inserted into the seating recess in a latchingmanner.

At the distal end of the height sensing element (which is also referredto as stylus), i.e. at the distal (free) end/end portion of theinsertion element/peg, the spring-loaded latching mechanism is attached,which locks the stylus in the seating recess of the saw block.Advantageously, the stylus remains rotatable about the insertion axis,allowing easy alignment of the sensing element.

In a more preferable embodiment, the latching mechanism is preferablyarranged in the insertion element itself and comprises a detent nosewhich, in the inserted state, engages behind the seating recess in sucha way that the height sensing element is axially retained therein.

The axial arresting is advantageously achieved by means of a“spring-loaded nose” which, when the stylus is inserted, isautomatically pushed back laterally due to its beveled distalcontact/sliding surface and, when fully inserted into the tool guidingdevice, latches in place in an undercut in the tool guiding device. The“spring-loaded nose” can additionally be retracted by hand and laterallyfrom the arresting position against its spring bias by means of a leveror an actuating button, thus cancelling the latching engagement. In thisstate, the stylus can be easily removed in an advantageous manner fromthe tool guiding device, i.e. from the saw block.

Furthermore, a fifth inventive idea of the present invention is toprovide an alignment device for a tibial resection guide, preferablycomprising the following components:

-   a clamping device (ankle shackle) preferably according to the first    inventive idea of the present invention for clamping the distal end    of a tibia of a patient;-   a tool guiding device/saw block for guiding a tool during the    resection of the tibia;-   a telescopic device or telescopic shaft preferably according to at    least one of the second to fourth main ideas of the invention, which    is connected or can be connected to the tool guiding device at its    proximal end portion and is connected or can be connected to the    clamping device at its distal end portion, and is designed to align    the devices with respect to the tibia, the telescopic device having    in its proximal region a drive device mount for selectively    receiving a proximal fixation unit or drive device, which is formed    by the shaft, at least partially designed as a hollow body, of the    telescopic device, preferably slide shaft/slide rod element.

As already mentioned above, the alignment device according to theinvention is converted from one solution variant to a second one by asimple instrumental addition. The two variants are the “anteriorfixation” and the “proximal fixation”.

The conversion is solved by placing an additional “proximal fixationunit”, namely the drive device, on top of the version “anteriorfixation”, thus allowing to apply the proximal fastening (version“proximal fixation”) to the “Eminentia intercondylaris tibiae”.

The “proximal fixation unit” essentially consists of the horizontalcantilever arm including the drive pin unit and of the vertical supportcolumn including the lever mechanism for clamping the unit to thealignment device or the shaft, in particular the slide shaft element.The “proximal fixation unit” is attached to the proximal end of thealignment device in the version “anterior fixation”. It has thefollowing functions:

-   Easy fixation and release of the "proximal fixation unit in the    proximal part of the version "anterior fixation"    -   The fixation is preferably performed by a        lever-spread-mechanism.    -   By actuating a lever (thumb pressure downwards), a rod is moved        upwards within the support column.    -   For this purpose, the rod is guided in a hole in the distal        shaft part (support column) of the “proximal fixation unit”.    -   At the distal end of the rod, a square element, beveled        proximally by e.g. 45°, is firmly attached.    -   Said square element abuts the distal end, e.g. also beveled by        45°, of the shaft of the “proximal fixation unit”, which        preferably has the identical square shape as the square element        on said rod.    -   Both square elements form the unit which is inserted into the        square shaft tube of the proximal end of the version “anterior        fixation” (in the region of the handle).    -   The preferred 45° bevels of the two square elements are arranged        to be mirror-inverted to each other.    -   If the more distally arranged square element is now pulled        toward proximal by the lever mechanism and the rod, a lateral        offset of said two square elements occurs due to the 45° bevels        arranged in reverse manner.    -   If this occurs when both elements are in the square tube, a        clamping and thus a fixation of the “proximal fixation unit” in        the proximal end (in the square tube) of the shaft of the        alignment device in the version “anterior fixation” will        inevitably occur.    -   By opening said lever mechanism, the clamping is released and        the “proximal fixation unit” can be removed in its entirety from        the alignment device with only one manual operation. The lever        for releasing is moved upwards with fingers (preferably the        middle finger and/or ring finger) when gripping the "proximal        fixation unit.-   Horizontal movability of the cantilever arm in the support column    with self-adhesion, if no to low sliding forces act from the    outside.    -   The movability of the cantilever arm guarantees that the        alignment device is compatible with tibial anatomies worldwide        and that the user can therefore set his intended slope at any        time.-   Securing against rotation and lateral displacement by fixation to    the Eminentia intercondylaris tibiae using preferably two drive    pins.-   Loosening of the pins is performed with an additional impact lever,    if necessary-   Guiding the saw block or saw block adapter in the longitudinal    direction of the shaft during the cutting height adjustment.    -   For the height adjustment of the saw block, the tibia saw block        adapter, attached to the proximal end of the alignment device        version “anterior fixation”, must be released for axial sliding        along the telescopic shaft and independently from the handle.    -   The release is achieved by actuating a corresponding locking        mechanism to release the coupling between the saw block adapter        and the handle. For example, the locking mechanism (pushbutton)        is attached laterally on the proximal end of the alignment        device.    -   The sliding knob assumes 2 positions in its function:        -   1. Position: Locking the tibia saw block adapter ≙ “anterior            fixation”        -   2. Position: Release of the tibia saw block adapter ≙            “proximal fixation”

Advantageously, the alignment device is consequently converted from onesolution variant to a second one by a simple instrumental addition,being the “anterior fixation” and the “proximal fixation unit” asdefined above.

Further advantageously, the drive device can be inserted at its distalend into the hollow body of the shaft, i.e. into the at least partiallyhollow and proximally open slide shaft element of the telescopic device,in such a way that clamping of the drive device in the hollow body/slideshaft element can be effected via said clamping mechanism. Thus,positive connections such as bolts, screws, etc. are preferablydispensed with, and only frictional connections are employed that can bemade quickly and easily.

According to a sixth main idea, the present invention preferablyconsists in providing an alignment device for a tibial resection guide,comprising the following components:

-   a clamping device preferably according to the first main idea of the    invention, comprising at least two clamping elements acting against    one another for clamping the distal end of the tibia of a patient,    which are attached to a cantilever designed to be inserted into a    foot clamp reception device,-   a tool guiding device for guiding a tool during the resection of the    tibia,-   a telescopic device preferably according to at least one of the    second to the fifth main idea of the invention, connected to the    tool guiding device and to the clamping device and designed to align    the device with respect to the tibia, the telescopic device having a    handle element designed to receive a slide shaft/slide rod element    slidably mounted therein, the alignment device comprising a first    slide shaft element/slide rod element having a first length and a    second slide shaft element/slide rod element having a second length,    the respective slide rod elements being provided to be inserted into    the handle element as required, wherein the respective slide rods    are connected, at their distal end, preferably perpendicular to the    foot clamp reception device, and the ratio of the first length of    the first slide rod element to the second length of the second slide    rod element is preferably between 1 and 1.5, more preferably between    1.1 and 1.3 and in particular is equal to 1.27, the length being    measured in each case from the proximal end of the slide rod to the    center of the foot clamp reception device, so that different lengths    of the tibia can be resected by each of the first and second slide    rods.

In other words, the sixth main idea of the present invention relates tothe general creation of possibilities for changing the length spectrumof an alignment device as cost-effectively as possible, preferably inaccordance with at least one of the first to fifth main ideas of theinvention in the context of a single alignment device. There areessentially two measures available for this purpose, which can be takentogether or independently of each other:

Firstly, there is the first possibility of providing an alignment deviceof the present type with a telescopic (extendable) shaft or a telescopicdevice, on the proximal end portion of which a saw block is mounted orcan be mounted and on the distal end portion of which a clamping deviceor foot clamp is arranged or can be attached. According to theinvention, the extendable shaft or telescopic device has a slide shaftelement/slide rod element (or simply slide rod), which is received in ahandle in an axially movable manner and can preferably be fixed relativeto the handle in a selected/selectable extension position by means of anarresting device (arresting screw). According to the invention, thisalignment device comprises a set of slide rods/slide shaft elements ofdifferent shaft/rod lengths (at least two slide rods with rod lengthsthat differ from each other), which are selectively interchangeable andcan be inserted telescopically into the handle in a selected manner.

In an advantageous manner, different lengths of the tibia, i.e.different leg lengths, can thus be resected. This is achieved byreplacing the slide rod, which is available in different lengths as apart of the available set of slide rods. Thus, all lengths of the tibiacan be resected in an advantageous manner using the alignment device.

Furthermore, the second possibility (which can be used separately or incombination with the above first possibility) is that the clampingelements of the foot clamp reception device are attached to thecantilever arm in a longitudinally offset manner, with the cantileverarm being able to be inserted into the foot clamp reception device in afirst position and in a second position by rotating it through 180°degrees, such that in the first position the clamping elements arealigned relative to the distal end of the alignment device and in thesecond position the clamping elements are aligned relative to theproximal end of the alignment device, so that a height offset of theclamping elements in the longitudinal direction is effected when thecantilever arm is inserted into the foot clamp reception device rotatedby 180° degrees from the first to the second position.

In other words, there is preferably provided an alignment device of thepresent kind with a telescopic (extendable) shaft or telescopic device,on the proximal end portion of which a saw block is mounted or can bemounted and on the distal end portion of which a clamping device orankle shackle device is arranged or can be attached. According to theinvention, the extendable shaft/telescopic device has a slide shaftelement/slide rod element (or simply slide rod), which is received in ahandle in an axially movable manner and can preferably be fixed relativeto the handle in a selected/selectable extension position by means of anarresting device (arresting screw). At the distal end portion of thetelescopic device, in particular of the slide rod element, areceptacle/support for mounting/attaching the clamping device/ankleshackle device is provided for this purpose.

The clamping device/ankle shackle device has an ankle shackle portion,preferably a Y- or V-shaped tibia contact block or mounting block (aspreferably already described with respect to the first main idea of theinvention), on which (the) clamping elements are preferably mountedaccording to the first main idea of the invention, the ankle shackledevice further having a coupling portion, preferably an insertion rod,which can be brought into engagement with the receptacle on the side ofthe slide rod.

According to the invention, the ankle shackle portion, in particular theclamping elements and/or the tibia contact block, is/are arrangedasymmetrically with respect to the coupling portion, in particular withrespect to the insertion rod, i.e. arranged to be offset in thelongitudinal direction of the telescopic device, in such a way that theankle shackle portion, in particular the clamping elements, are arrangedeither above (proximal) or below (distal) the coupling portion (asviewed in the direction of the shaft), depending on the direction ofrotation of the coupling portion, when the coupling portion isinserted/engaged in/with the shaft-side receptacle. In this way, thedistance between the proximal saw block and the ankle shackle portion,in particular the clamping elements, can be made larger or smaller asdesired (depending on the asymmetry/longitudinal offset) by means of acorresponding rotational orientation of the coupling portion during itsassembly.

In a particularly preferred embodiment, the height offset of the footclamp reception or insertion device is measured from the center of thefoot clamp reception device to the respective edge point of the clampingelements. In the first position towards the distal end, this distance ispreferably between 10 mm and 20 mm and in particular is equal to 15 mm.By the possibility of turning the foot clamp reception device by 180°,an additional length adjustability in both directions, preferably by 15mm, is achieved. On the whole, the combination of the different lengthsof the slide rods with the reversible foot clamp reception or insertiondevice provides an alignment device which is very flexible in theadjustment of the length and which can thus be used for the worldwidetibia sizes.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is explained in more detail below by means ofpreferred embodiments with reference to the accompanying drawings.

FIG. 1 shows a perspective view of an alignment device of the inventionaccording to a first preferred embodiment,

FIG. 2 shows a perspective exploded view of a second preferredembodiment of FIG. 1 ,

FIG. 3 shows a side view of the alignment device of FIGS. 1 and 2 ,

FIG. 4 shows a perspective view of an alignment device of the inventionaccording to a further preferred embodiment,

FIG. 5 shows a perspective view of a tool guiding device,

FIG. 6 shows a perspective side view of the tool guiding device of FIG.5 ,

FIG. 7 shows a perspective frontal view of the tool guiding device ofFIG. 5 ,

FIG. 8 shows a perspective view of a second embodiment of the toolguiding device,

FIG. 9 shows a perspective side view of the second embodiment of thetool guiding device of FIG. 8 ,

FIG. 10 shows a perspective frontal view of the second embodiment of thetool guiding device of FIG. 8 ,

FIG. 11 shows a perspective view of the clamping device according to theinvention with closed clamping elements,

FIG. 12 shows a plan view of the clamping device according to theinvention with closed clamping elements,

FIG. 13 a shows a perspective view of the clamping device according tothe invention with open clamping elements,

FIG. 13 b shows a further perspective view of the clamping deviceaccording to the invention with open clamping elements,

FIG. 14 shows a ratchet mechanism of the clamping device according tothe invention of FIGS. 13 a and 13 b ,

FIG. 15 shows the clamping device according to the invention of FIGS. 13a and 13 b with inserted tibia and with open clamping elements,

FIG. 16 shows the clamping device according to the invention of FIGS. 13a and 13 b with inserted Tibia and with closed clamping elements,

FIGS. 17 a, 17 b, 18 and 19 show the ratchet mechanisms of the clampingdevice in various adjustments,

FIGS. 20-23 show the decoupling device according to the invention incombination with the tool guiding device in various positions,

FIG. 24 shows the draw-off direction of the alignment device accordingto the invention,

FIG. 25 shows a perspective view of the decoupling device according tothe invention,

FIG. 26 shows a further perspective view of the alignment deviceaccording to the invention,

FIG. 27 shows a first perspective view of the securing element accordingto the invention,

FIG. 28 shows a further perspective view of the securing elementaccording to the invention,

FIGS. 29-35 show various detail views of the securing element accordingto the invention,

FIG. 36 shows a perspective view of the contact device according to theinvention,

FIG. 37 shows a further perspective view of the contact device accordingto the invention,

FIG. 38 and FIG. 39 show further perspective views of the contact deviceaccording to the invention,

FIG. 40 and FIG. 41 show detail views of the contact device according tothe invention,

FIGS. 42-44 show further perspective views of the contact deviceaccording to the invention,

FIG. 45 shows a first perspective view of the drive device according tothe invention,

FIG. 46 shows a further perspective view of the drive device accordingto the invention,

FIGS. 47-51 show detail views of the drive device according to theinvention,

FIGS. 52-55 show perspective views of the alignment device according tothe invention,

FIG. 56 shows the slide rods in different lengths,

FIG. 57 and FIG. 58 show the clamping device according to the invention,and

FIGS. 59-62 show further perspective views of the alignment deviceaccording to the invention.

The drawings are merely schematic in nature and are intended only to aidunderstanding of the invention. Identical elements are provided with thesame reference signs. The features of the various embodiments can beinterchanged.

DETAILED DESCRIPTION

FIG. 1 shows an alignment device preferably in the form of anextramedullary tibia alignment device 1 according to the presentinvention in an “anterior fixation version” comprising a proximal region52 and a distal region 54. The proximal region 52 is defined as theregion facing towards the patient’s body, and the distal region 54 isdefined as the region facing away from the patient’s body. The distalregion 54 is therefore the region where, for example, the patient’sfoot/ankle is located.

Accordingly, the alignment device 1 comprises/has, among other things:

-   a telescopic device 10, which forms the central part of the    alignment device 1 and has a proximal handle 14, a    (telescopic/extendable) distal slide shaft element 11 supported so    as to be axially movable in the handle 14, and a distal    receptacle/connection point 5 for an ankle shackle/clamping device    2,-   a distal ankle shackle/clamping device 2 which is insertable (is    inserted) into the distal receptacle 5 or can be engaged with it,-   a proximal (mounting) saw block adapter/decoupling device 12, which    is releasably coupled/can be releasably coupled to the handle 14    preferably at the proximal end face thereof,-   a saw block/tool guiding device 8 releasably coupled to the saw    block adapter 12, and preferably-   a contact device (adjustable height feeler/contact device) 6, which    is releasably coupled to the saw block 8 at the distal side thereof.

In the distal region of the alignment device 1, the clamping device 2 isarranged, which includes/comprises clamping elements 4 and 4 a, whichare arcuately shaped and thus form an oval-shaped region 22 betweenthem, which is provided to clamp or hold the tibia. The telescopicdevice 10 extends along a longitudinal axis 20. In the proximal regionof the telescopic device 10, the handle 14 is arranged, at the distalend/end portion of which the saw block adapter/decoupling device 12 isconnected/arranged thereto (directly or indirectly) and thus selectivelyforms a unit with the handle 14. Provided on the saw block adapter 12 isan actuating/pressure element 16 which is preferably arranged/aligned atan angle A to the handle 14. Hence, said pressure element points in thedirection toward the proximal region 52 (upwards), so that a treatingphysician can enclose the handle 14 with the fingers of one hand andsimultaneously operate the pressure element 16 with his thumb. In theproximal region 52, the saw block (also to be referred to as a toolguiding device) 8 is arranged, to which the contact device 6 isdetachably attached. The pressure element 16 acts on the decouplingdevice (saw block adapter) 12, which is provided to separate thetelescopic device 10 from the tool guiding device (saw block) 8. As soonas the tool guiding device 8 is firmly connected to the tibia, it can bedecoupled from the telescopic device 10 by triggering the decouplingdevice 12 via the pressure element 16.

FIG. 2 shows the alignment device 1 in a “proximal fixation version” inexploded view.

In accordance with FIG. 1 , the alignment device 1 has in its centralpart the telescopic device 10, which in its proximal region 52 is inturn connected/connectable to the tool guiding device/saw block 8via thesaw block adapter 12, to which the contact device 6 isattached/attachable. Furthermore, a drive device 202 is additionallyattached/attachable to the telescopic device 10 (in adaptive/selectivemanner). In the distal region 54, the clamping device 2 comprising theclamping elements 4, 4 a is attached/attachable to the telescopic device10. In this respect, the alignment device 1 according to FIG. 2corresponds conceptually to that according to FIG. 1 , with thedifference that the drive device 202 is additionally mounted on thetelescopic device 10 at the proximal end portion thereof.

FIG. 3 shows the alignment device 1 according to FIG. 2 in a side viewas well as in an exploded view, and FIG. 4 shows the alignment device 1in a fully assembled state. In particular in the illustration accordingto FIG. 3 , the individual interfaces on the alignment device 1according to the invention are at least partially recognizable.Accordingly, the saw block 8 can be selectively engaged with the sawblock adapter/decoupling device 12, the contact device 6 can beselectively engaged with the saw block 8, and the drive device 202 canbe selectively engaged with the telescopic device 10 and, in particular,the distal slide shaft element 11 at its proximal end/end portion, whichfor this purpose penetrates the handle 14 axially toward proximal(completely). In FIG. 4 , it is shown how the drive device 202 isinserted into the proximal end portion of the slide shaft element 11.

FIG. 5 to FIG. 10 show different views of the tool guiding device/sawblock 8 and of the saw block adapter/decoupling device 12. In FIG. 5 ,the tool guiding device 8 is shown together with the decoupling device12, which includes the pressure element/pushbutton 16. The tool guidingdevice/saw block 8 preferably has lateral drive holes 300 that can beused to fix the saw block 8 to the tibia by screws or nails. The toolguiding device/saw block 8 is designed to receive a tool/saw forresection of the tibia in guiding manner, for which a tool guideslot/saw slot 302 is formed in the saw block 8. FIG. 6 shows the toolguiding device 8 with the tool guide slot 302 aligned in the horizontaldirection when fixed to the tibia, in a state separated from the sawblock adapter 12. FIG. 7 shows the tool guiding device 8 with a femalecoupling portion, in the present case with two vertically spacedreceiving holes 28 and an additional drive slot 303, which is providedto receive fasteners or nails for driving into the tibia.

The tool guiding device, i.e. the saw block 8, has following functionsor functional elements:

-   Guiding a saw blade for the bone section within the guide slot 302,-   Providing drive/fixing holes 300 and/or the drive slot 303 for    fastening the tool guiding device 8, i.e. the saw block, to the bone    and, if necessary, for correcting the cutting height by up to +/- 4    mm,-   Providing an adapter interface (female coupling portion with    receiving holes 28) for mounting on the alignment device/telescopic    device 10, and-   Providing an adapter interface for mounting the contact    device/cutting height feeler 6.

In addition, FIGS. 5 and 8 , for example, show different versions for asaw block 8 according to the invention, namely a version (FIG. 5 ) foran “anterior fixation variant” and a version (FIG. 8 ) for a “proximalfixation variant”, in which the adapter interface (insertion hole) forthe cutting height feeler 6 is offset with respect to the versionaccording to FIG. 5 or two adapter interfaces are provided for bothvariants.

FIG. 11 to FIG. 13 b show perspective views of the clamping device 2.FIG. 13 a shows the clamping device 2, which has the two clampingelements/clamping arms 4 and 4 a. The clamping elements 4 and 4 a areeach arcuately shaped and gently taper at their respective free ends(bent outward), so that the clamping elements 4, 4 a can be pulled offthe tibia or ankle (resiliently) without injury and without the freeclamping arm ends being able to scratch the patient’s skin.

Specifically, the clamping device 2 has a mounting block in the form ofa T-piece 92 with a preferably cross-sectionally square (rectangular)insertion rod 93 and a hollow crossbeam 95, in which a spindlemechanism/spindle 90 is mounted, which can be rotated about itslongitudinal axis by means of rotary knobs 304 arranged on the end faceof the crossbeam 95. A carriage (tibia contact block) 86 is supported onthe crossbeam 95, which is engaged by the spindle 90, so that thecarriage 86 can be moved back and forth along the crossbeam 95 duringmanual rotation of the spindle 90 by means of the rotary knobs 304. Thecarriage 86 further comprises a central/central contact area 78 as wellas two contact arms 82 aligned in a V-shape with respect to each other,at the free end portions of which a ratchet mechanism 76 isarranged/installed in each case, where one clamping element 4, 4 aengages in each case in such a way that the clamping elements 4, 4 a arepivotably mounted on the contact arms 82 and can be pivoted manuallytowards each other (in the closing direction), the respectivelyassociated ratchet mechanism 76 initially preventing a pivoting back (inthe opening direction).

Furthermore, each ratchet mechanism 76 has a biasing spring 77 (theseare shown in particular in FIG. 11 as leg springs), which bias theassociated clamping elements 4, 4 a in the opening direction. Finally,each ratchet mechanism 76 has a ratchet lever 84 via which theassociated ratchet mechanism 76 can be unlocked/released.

The clamping elements 4 and 4 a are made of a pre-bent (leaf) springsteel and consist of several prongs or fingers 62 arranged next to eachother and spaced apart in the manner of a fork 60 so that theprongs/fingers 62 of the clamping elements 4, 4 a facing each other canengage into one another in an overlapping manner when they are swiveledin the closing direction, thus ensuring secure fixation to the tibia 3.

FIG. 11 shows the clamping device 2 with the closed clamping elements 4and 4 a, which engage into one another in such a way that a tibia 3 canbe sufficiently clamped or held thereon. To preload the clampingelements 4 and 4 a, the ratchet levers 84 are first pressed in amovement directed away from each other, as a result of which latchingpawls (these are shown schematically in FIG. 11 as pawls/teeth formedintegrally with the ratchet levers 84) engage in an external toothing onthe respective clamping elements 4, 4 a. If the clamping elements 4, 4 aare to be released, the ratchet levers 84 are pressed slightly inwards(towards each other) (see FIG. 11 ), which disengages the latching pawlsfrom the associated clamping elements 4, 4 a and thus eliminates theratchet effect. Via the spindle mechanism 90, to which the rotary knobs304 are attached, the clamping elements 4, 4 a can be moved in bothdirections along the crossbeam 95 via the common carriage 86. Thespindle mechanism 90 is integrated in the crossbeam 95, as alreadyexplained above. In this way, the clamping elements 4, 4 a can beoptimally aligned in the transverse direction of the tibia in the statealready embracing the tibia, without exposing the patient or thephysician to a risk of injury, e.g. as a result of protruding parts ofthe spindle, etc.

The T-piece 92, in cooperation with the carriage 86 and the contact arms82 arranged thereon, forms a substantially Y-shaped tibia contact blockassembly unit which can be inserted into a corresponding distal ankleshackle receptacle 5 on the side of the telescopic device 10.

For this purpose, the T-piece 92 forms the mandrel/insertion rod 93,which is preferably rectangular in cross-section and has alatching/gripping structure 94 on at least two longitudinal sides facingaway from each other, by means of which the entire clamping device 2 orassembly unit is movably fastened or can be movably fastened to thetelescopic device 10 or the receptacle 5 thereof.

FIG. 12 shows the clamping device 2 in plan view and in the closedstate, with the oval-shaped region 22 for receiving the tibia (shownschematically in FIG. 12 ) being formed between the clamping elements 4,4 a. Here, the tibia 3 is received by the V-shaped contact block/element86 including the lateral contact arms 82 and the clamping elements 4, 4a. Between the V-shaped contact block 86 and the lateral contact arms82, an angle C is formed in the central contact area 78, which amountsto preferably 45° on each side (i.e. the two contact arms 82 enclose acommon angle of approx. 90°). Thus, a particularly ergonomic contact ofthe tibia is created in the V-shaped contact block 86.

Furthermore, FIG. 12 shows the directions of force application to thetibia 3 that are achievable with the ankle shackle 2 according to theinvention.

Accordingly, the two clamping elements 4, 4 a completely enclose thetibia in that their prongs/fingers intersect/get caught/overlap witheach other at the posterior side of the tibia, thus pressing the tibiaagainst the frontal contact block/carriage 86. Since the clampingelements 4, 4 a are pre-bent and also resilient, they can at the sametime also apply a clamping force to the tibia from the sides,effectively chucking it all around. This is clearly illustrated by theforce arrows in FIG. 12 .

FIG. 13 a shows the clamping device 2 with the clamping elements 4, 4 ain the open position so that a tibia can be inserted. Moving the ratchetlevers 84 towards each other releases the clamping elements 4, 4 a orthe ratchet mechanism, so that the clamping elements 4, 4 a can bebrought into an open position due to the internal spring bias, whereasmoving the two ratchet levers 84 away from each other reactivates theratchet mechanism so that the clamping elements 4, 4 a can beindividually brought into a closed position and latched in place there.

As already explained above, the rotary knob(s) 304 is/are provided toeffect a lateral adjustability of the carriage/tibia contact block 86and the clamping elements 4, 4 a mounted thereon, and the spindle 90,which can be actuated by means of the rotary knobs 304 for displacingthe carriage 86 is integrated into the T-piece 92 or the crossbeam 95.

FIG. 13 b shows the clamping device 2 together with the respectiveclamping elements 4 and 4 a, which in turn are designed to engage intoeach other through the respective forks 60, so that the tibia is clampedalmost all around and, if necessary, an almost constant chucking forceis effected in the circumferential direction.

FIG. 14 shows the clamping device 2 and a hinge area 86 of a clampingelement 4 and of the contact block/carriage 86. The clamping element 4is coupled to the ratchet mechanism 76, which can be released via theratchet lever 84, while only one ratchet lever 84 is shown in FIG. 14 .The latching pawl (without reference sign) of the ratchet lever 84 canbe seen, which engages in an external toothing in the hinge area of theclamping element 4 in a spring-loaded manner, as well as the ratchetlever 84 integrally connected thereto for disengaging the latching pawlfrom the external toothing. Further, the rotary knob 304 is illustrated,by means of which the tibia contact block 86 is adjustable/movable inthe lateral direction.

FIG. 15 shows a top view of the clamping device 2 in the open state. Theclamping elements 4, 4 a are coupled to the ratchet mechanism 76 viatheir respective (inner/close-to-hinge) ends/hinge areas 68. Theclamping elements 4, 4 a are preferably made of thin sheet metal orother elastic material. At their free ends/tips 66, the clampingelements 4, 4 a each point (radially) outward (are bent outward) toallow injury-free removal or withdrawal of the respective clampingelements 4, 4 a from the tibia. The ends 68 of the clamping elements 4,4 a close to the hinge are preferably reinforced with a plastic part(reinforcing element) 70 (or sheathed with plastics), in particular tobring about a gentle introduction of moments into the further structurein such a way that the clamping elements 4, 4 a are sufficientlyfatigue-resistant.

FIG. 16 also shows the clamping elements 4, 4 a in the closed state.Between the clamping elements 4, 4 a, the oval-shaped region 22 forreceiving the tibia or ankle is formed. The clamping elements 4, 4 a,the V-shaped contact element/contact block/carriage 86 and therespective lateral contact areas/contact arms 82 of the contact block 86create the force effect 308 acting circumferentially around the tibia.Specifically, the clamping elements 4, 4 a are designed such that theforce effect 308 acts on the tibia at several different locations in thecircumferential direction of the tibia so that the tibia is firmly heldall around.

From FIG. 13 b in conjunction with, for example, FIG. 3 , the spatialarrangement of the clamping arms 4, 4 a with respect to the contactblock 86 or the T-piece 92 can be seen.

Consequently, the clamping arms 4, 4 a (in the manner of a shovel) arearranged offset in height with respect to the T-piece 92, i.e. they donot lie in the same plane as the T-piece 92. This has the directconsequence that in the case of a rotary position according to FIG. 3 ,the clamping arms 4, 4 a are located below the T-piece, whereas in thecase that the T-piece 92 is rotated by 180°, the clamping arms 4, 4 acome to lie above the T-piece 92.

At this point, it should be recalled that the insertion mandrel 93according to FIG. 13 a is a square profile and the receptacle 5 at thedistal end of the telescopic device 10 consequently forms a rectangularreception duct into which the insertion mandrel 93 is inserted andlatched in place therein. This means that depending on the direction ofrotation of the T-piece 92, the distance between the clamping arms 4, 4a (above or below the T-piece 92) and the proximally arranged saw block8 is increased or decreased, as a result of which the overall lengthspectrum of the telescopic device 10 can be additionally reduced orincreased on the whole.

FIGS. 17 a, 17 b, 18 and 19 each show the clamping device 2 incross-section. FIG. 17 a , b show the clamping elements 4, 4 a, whichare coupled in each case to the ratchet mechanism 76 via theclose-to-hinge ends 68 of the clamping elements 4, 4 a. FIG. 17 a showsthe open clamping position and FIG. 17 b shows the clamping elements 4,4 a in the closed clamping position. The springs 77, which preload theclamping elements 4, 4 a in the opening direction, and the two ratchetmechanisms 76 with adjoining ratchet levers 84 for manual, individualdisabling of the ratchet action can be seen.

FIGS. 18 and 19 show an enlarged view of the clamping device 2 with therespective clamping elements 4, 4 a, which are coupled to the respectiveratchet mechanism 76. In addition, the relaxed return spring 77 of therespective ratchet mechanism 76 can be seen in each case.

The clamping device 2, which is also referred to as a foot clamp, isdesigned such that the telescopic device 10 can be pulled off both atthe proximal adapter interface 12 of the tibia saw block 8 and, in aparticularly simple handling action, from the patient’s tibia in a waythat is gentle on the tissue (i.e. atraumatic), for which purpose thespring elasticity of the clamping arms 4, 4 a is exploited. This meansthat in case a surgeon wants to remove the telescopic device 10 from thetibia while leaving the saw block 8 on the tibia, he or she only has topress the pushbutton 16 to uncouple the saw block 8 from the telescopicdevice 10 and at the same time simply pull off the clamping device 2(without actuating the ratchet lever 84).

Furthermore, the spring elasticity of the clamping arms 4, 4 a resultsin an almost constant clamping force over the circumference of thetibia, so that hematomas due to punctual application of force can beavoided. The clamping device 2, i.e. the foot clamp, is particularlydistinguished for this object by the fact that

-   the clamping elements 4, 4 a, i.e. the retaining elements of the    ankle shackle 2, are sufficiently elastic so that they can be easily    pulled off the distal tibia without operating a release mechanism,    and that at the same time they have a sufficiently high rotational    and translational stability against unintentional adjustment of the    ETA, and that-   the ratchet mechanism 76 can also be opened manually by means of the    ratchet levers 84.

The ratchet mechanism 76 is made operative/inoperative via therespective ratchet lever 84. Furthermore, it is possible not to simplypull the clamping elements 4, 4 a off the tibia, but to release theratchet lever 84. The two clamping elements 4, 4 a are thenautomatically opened by the return spring 77 after actuation of theratchet levers 84 and thus release the tibia.

As already explained above, the adapter interface for the tibia sawblock 8, i.e. for the tool guiding device, is designed in such a waythat the saw block adapter 12 forming the adapter interface can beactuated by simply pressing the pushbutton 16 with the thumb to releasethe telescopic device 10 from the saw block 8, as a result of which aretaining mechanism 18 (described in more detail below) releases the sawblock 8. Due to the variants described above with regard to the sawblock 8 as well as the clamping device 2, it is now possible, afterfastening the saw block 8 to the tibia and operating the saw blockadapter 12 (i.e. actuating the retaining mechanism 18), to pull thetelescopic device 10 including adapter 12 and clamping device 2 off thepatient’s tibia with one (single) hand and a thumb pressure as well asby utilizing the spring elasticity of the clamping arms 4, 4 a, withoutany further operating action being necessary. This facilitates thehandling of the entire alignment device 1 to a considerable extent.

FIG. 20 to FIG. 23 show different perspective views of the tool guidingdevice/saw block 8 in combination with the decoupling device/saw blockadapter 12. In FIG. 20 , the tool guiding device 8 is (selectively)attached to/coupled in the decoupling device 12. The decoupling device12 has the retaining mechanism 18 including the pressure element 16,which preferably has a relief-like surface 50. The thumb pressure forceof the respective treating physician presses on the relief-like surface50 of the pressure element 16.

FIG. 21 shows the interaction of the tool guiding device 8 with thedecoupling device 12. Specifically, the tool guiding device 8 has anadapter socket 36, which in turn has a plurality of female receivingelements 28. It is preferred that each of the female receiving elements28 is a recess/bore in the adapter socket 36, which are provided topositively receive the respective male receivingelements/protrusions/pins 26 of the decoupling device 12. The fitting ofthe respective male receiving elements 26 in the respective femalereceiving elements 28 ensures a secure support of the tool guidingdevice 8 on the decoupling device 12 in all three spatial directions.The decoupling device 12 also mounts the retaining mechanism 18 in theform of a retaining bracket or hook element 30, which is provided toenclose the adapter socket 36 of the tool guiding device 8 and to getcaught in/on it at a corresponding undercut 44.

FIG. 22 shows a side view of the tool guiding device 8 and the saw blockadapter 12 in the coupled state. Accordingly, the securing bracket 30preferably consists of a sheet metal component which is bent so as toform a substantially U-shaped hollow profile, the two, respectivelyfree-ending webs/side flanks of the U-profile, being formed into hooksand the connecting web of the U-profile being formed into the pressureelement 16. This securing bracket 30 formed in this way is hinged to abase body 24 of the saw block adapter 12 on both sides thereof (i.e. thebase body 24 is received in the hollow U-profile). The hollow U-profilethus forms a kind of rocker with the pressure element 16 on one side andthe hooks on the other side of the rocker hinge. In the coupled stateaccording to FIG. 22 , the hooks of the securing bracket 30 engage withthe undercuts 44 in the form of bolt- or pin-like protrusions on the sawblock 8, in particular on its mounting/adapter socket 36, and thusretain it on the adapter interface of the saw block adapter 12.

In addition, FIG. 22 indicates a lateral actuation button on the basebody 24 of the saw block adapter 12, which interacts with a latchingmechanism (symbolically shown on the lower end face of the saw blockadapter 12), by means of which the saw block adapter 12 can be coupledto the handle 14 at the upper end face thereof (upper handle section) inorder to selectively form a unit with the handle 14, as shown forexample in FIG. 15 .

FIG. 23 shows the mode of operation of the decoupling device/saw blockadapter 12 (in particular of the retaining mechanism) and of the toolguiding device/saw block 8, which is to be coupled to the base body 24of the decoupling device 12.

It can be seen that by actuating the pressure element 16 by thumbpressure, the securing bracket 30 can be pivoted, while its hooks can belifted. In this state, the saw block 8 can be placed onto the adapterinterface of the decoupling device 12, while the male protrusions/pegs26 are inserted into the female recesses/holes 28 according to theplug-and-socket principle. Finally, the pressure element 16 is released,whereupon the hooks of the securing bracket 30 (by gravity orspring-loaded) swing downward, engaging behind the protrusions 44 on thesaw block 8 (see FIG. 22 ). The decoupling device 12 is separated fromthe saw block 8 in the corresponding reverse manner.

FIG. 24 shows the removal direction of the alignment device 1 (thetelescopic device 10 together with the foot clamp 2 and adapter 12) whenthe tool guiding device 8 is/remains attached to the tibia and is thusto be separated from the telescopic device 10. The treating physicianpresses with the force of his thumb on the relief-like surface 50 of thepressure element 16 (as a result of which the retaining bracket 30releases the saw block 8) and simply pulls the telescopic device 10together with the clamping device 2 off the patient’s tibia. In sodoing, the clamping device 2 is not opened separately, but the clampingelements 4, 4 a are spread open (automatically) due to their springelasticity during removal. The indicated hand 322 of the treatingphysician encloses here the telescopic device 10 or the handle 14.

FIG. 25 shows the hand 322 of the treating physician, which effects thethumb pressure force on the pressure element 16 of the telescopic device10. The fingers of the hand 322 of the treating physician embrace thetelescopic device 10 at the handle 14.

FIGS. 26 and 27 show the alignment device 1 according to the presentinvention with the telescopic device 10 according to a “proximalfixation variant”, wherein in the distal region of the telescopic device10 again the clamping device 2 preferably according to the abovedescription is provided and in the proximal region again the toolguiding device 8 preferably according to the above description isarranged via the adapter 12, to which preferably the contact device 6 isattached/attachable. The transverse direction 32 indicated in FIGS. 26and 27 means a direction of approach to the tibia of a patient.

An arresting or securing element 104 is provided on the telescopicdevice 10 (in all fixation variants), which can preferably be insertedinto the telescopic device 10 upstream of the alignment device 1 as seenin this transverse direction 32. The securing element 104 is provided,among other things, to secure the telescopic device 10 in variouspositions in a self-locking manner in a selected length position and/orto allow it to be pulled apart freely. The securing element 104 isfurther provided to be inserted in the transverse direction 32 into areceiving element/receiving portion 100 formed on the handle 14.Further, a locking element 112 is arranged on the receiving portion 100,which is designed to be manually moved into a release position in whichthe securing element 104 is removable from the receiving portion 100,whereas the locking element 112 holds the securing element 104 in thereceiving portion 100 in an (unactuated) latching position.

FIG. 28 shows the slide rod element 11 in an enlarged view, according towhich, on a side facing the securing element 104, a longitudinalgroove-shaped recess (hereinafter referred to as longitudinal groove)118 is formed on the slide rod element 11, which is distally andproximally limited by an end stop defining the minimum and maximumextension position (telescopic stroke) when the securing element 104 isin sliding engagement with the longitudinal groove 118.

FIG. 29 to FIG. 35 show various detail views of the securing element104.

FIG. 29 shows the securing element 104 in side view, which is providedto be inserted into the corresponding receiving portion 100 on thetelescopic device 10 and retained therein by means of the lockingelement 112. The corresponding receiving portion 100 is provided at thedistal end portion of the handle element 14. The handle element 14encloses the slide rod element 11. Also clearly visible in FIG. 29 is apeg 116 projecting radially (downward) from the securing element 104,which is used as an engagement element/undercut for the locking element112. Other latching engagement solutions are of course also conceivable,such as a bayonet lock or a screw connection, etc.

FIG. 30 shows the receiving portion 100 together with the lockingelement 112 and the securing element 104 in a partial cross-section.Accordingly, the securing element 104 generally consists of aspring-biased inner bolt 120, which is axially movably supported in arotary knob 102 to engage into the longitudinal groove 118 of the sliderod element 11, and of a preferably sleeve-shaped housing 114 forrotatably receiving the rotary knob 102 for applying an arresting forceto the slide rod element 11 while bypassing the spring bias or inparallel with the spring bias.

FIGS. 31 and 32 show the locking element 104 in detail, which isinserted into the receiving portion 100 of the handle 14. Accordingly, aslide block (without reference sign) is received in the longitudinalgroove 118 of the slide rod 11, in/on which the bolt 120 is axiallysupported. The bolt 120 has/forms a spring plate in its central portion,on which in turn a helical spring 124 is supported in order to apply apretensioning force to the bolt 120 in the direction towards the slideblock. The spring plate is simultaneously used as a stop element thatstrikes against a shoulder in the rotary knob 102, preventing the bolt120 and the spring 124 from falling out of the rotary knob 102. The bolt120 as well as the biasing spring 124 are received in the rotary knob102 in its axial direction, which is axially inserted/screwed into thepreferably sleeve-shaped housing 114, which in turn is inserted into thereceiving portion 100 and held/secured therein by means of the lockingelement 112 (see in particular FIG. 31 ). A set screw 122 is screwedinto the rotary knob 102 at the end face (at its free end face), whichis used as an abutment for the biasing spring 124. Accordingly, if theset screw 122 is turned within the rotary knob 102, the spring bias onthe bolt 120 (within the rotary knob) can be changed in this manner.

In addition, the bolt 120 has a coil portion 121 that extends from thespring plate toward the set screw 122 and is surrounded by the biasingspring 124, thus guiding the biasing spring 124.

FIG. 33 shows the securing element 104 with its adjusting element/setscrew 122, e.g. its adjusting screw, which is provided for adjusting thepretensioning forces acting on the bolt (clamping pin) 120. Furthermore,the locking element 112 can be seen, which effects the locking of thesecuring element 104 in the receiving portion 100 of the handle 14. Inthe lower area of FIG. 33 , the slide rod element 11 is shown, whichshows the (upper) stop portion 128 of the groove-shaped recess 118,which represents one of the two maximum extension positions 128, 130 ofthe slide rod element 11 with respect to the handle 14.

The mode of operation of the securing element 104 is briefly explainedbelow with reference to FIGS. 31 to 35 :

First, the securing element 104 is inserted into the receiving portion100 (into a bore formed therein), preferably in a sliding manner, andits sleeve-shaped housing 114 is secured in a rotationally and axiallyfixed manner by means of the locking element 112. In this state, thebolt/clamping pin 120 within the rotary knob 104 projects into thelongitudinal groove 118 of the slide rod element 11 and applies acompressive force thereto (indirectly via the slide block received inthe longitudinal groove 118) as a function of the preload force of thespring 124. In this manner, the preload force of the spring 124 can beincreased and/or decreased by turning the set screw 122 within therotary knob 104 to thereby change the frictional force between the sliderod 11 and the bolt 120 of the securing element 104. This allows, forexample, to reduce the friction to virtually zero or to increase it suchthat at least any displacement of the current stroke position of thetelescopic device 10 due to gravity is avoided.

In order to fix (freeze) the stroke position, the rotary knob 104 can befurther screwed into the sleeve-shaped housing 114, as a result of whichthe rotary knob 104, as from a certain screw-in position in the housing114, presses directly, i.e. in concrete terms via the coil portion 121of the bolt 120 (which is now axially supported on the set screw 122 inthe rotary knob 102) on the slide block and presses/braces the latterdirectly against the slide rod 11 while bypassing the spring bias.

In the following, the height sensing device (also referred to as aheight arresting or height adjustment unit) 6 is described withreference to FIGS. 36 to 44 .

FIG. 36 shows the tool guiding device/saw block 8 preferably asdescribed above, which comprises/has a seating recess/bore 150 intowhich the height sensing element/height adjustment unit 6 can beselectively inserted. In this context, the tool guiding device 8 hasonly one or more seating bore(s)/seating recess(es) 150, while it is tobe noted at this point that a side notch with a clamping strap, amagnetic holder or the like can also be provided instead. The at leastone seating recess 150 forms part of an adapter interface 334 betweenthe tool guiding device/saw block 8 and the height adjustment unit 6.

In principle, the height adjustment unit 6 essentially consists of

-   a contact tip 166 mounted or formed on a contact arm 338 (together    forming a height sensing assembly 152),-   a spindle mechanism 168, on which the contact arm 338 is supported    for at least one height adjustment, and-   an insertion mandrel/shaft 156 preferably with a latching    device/latching mechanism 154 as a further part of the adapter    interface 334 for coming into engagement with the seating recess 150    from a top side 151 of the saw block 8.

FIG. 37 shows a perspective view of the height adjustment unit 6according to the present invention. Accordingly, the height adjustmentunit 6 has a horizontal movability degree of freedom 346, a verticaladjustment degree of freedom 340 and a rotational degree of freedom 348.For this purpose, the height adjustment unit 6 has the insertionmandrel/shaft 156, which is preferably designed as a hollow shaft andcan thus accommodate the latching device 154 therein, which can bebrought into undercutting operative engagement with the seating recess150 on the side of the saw block 8 for axially fixing the heightadjustment unit 6 on the saw block 8. For this purpose, a spring-biaseddetent nose 160 is provided in the insertion mandrel 156, whichprotrudes laterally/radially beyond the circumference of the shaft 156and can be retracted into the insertion mandrel 156 by means of anactuating button 158 in order to release a detent engagement with thesaw block 8. The rotational degree of freedom 348 is thus effected bythe rotational freedom of the insertion mandrel/shaft 156 in thereceiving bore 150 of the tibia saw block 8.

The contact arm 338 is provided with an elongated hole (see FIG. 37 ),which is penetrated by the spindle mechanism/spindle 168 (sliding/free),to which the contact arm 338 is coupled via an interposed frictionalelement/holding carriage 354, which holds the contact arm 338 underfriction but longitudinally movably (in extendable manner) on thespindle mechanism 168. The horizontal movability degree of freedom 346is thus caused by the horizontal movability of the height sensingassembly 152 or contact arm 338 on the spindle mechanism 168 (via thefrictional element 354).

FIG. 38 shows the height sensing element 6 in side view, which isprovided to be inserted into the tool guiding device 8. Accordingly, theheight sensing element 6 has, on its lower side (facing the saw block8), the insertion mandrel 156 and the actuating element in the form of alever 158 which, in the unactuated state, bears against a lever stop(without reference sign) arranged or formed on the insertion mandrel156. Further, to contact the bony landmark of the tibia, the contact tip166 is provided at the outer (proximal) end of the contact arm 338.Finally, the spindle mechanism is shown with a spindle/spiral 168axially coupled to the insertion mandrel 156 and carrying the frictionalelement 354 including the contact arm 338 in its central portion.

FIGS. 39 and 40 show a perspective view of the saw block/tool guidingdevice 8, in which the height adjustment unit 6 is already inserted. Thespindle mechanism of the height adjustment unit 6 has the spindle/spiralelement 168 already indicated above as well as a spiral wheel 172, whichis provided/mounted on the spiral element 168. The spiral wheel 172 iscoupled in a relatively rotatable manner with the frictional element354, so that the latter (including the contact arm 338) is held (axiallymovable) on the spindle 168 via the spiral wheel 172.

A detail of FIG. 40 is shown in FIG. 41 . FIG. 41 shows the detentdevice 154 with the detent nose 160, which is inserted into the seatingrecess 150 on the saw block 8. Furthermore, a spring element 164 can beseen which is arranged between the lever stop and the actuating lever158 for actuating the detent nose 160 and biases the lever 158 into aposition in which the detent nose 160 is in a detent engagement position(radially protruding according to FIG. 41 ). Specifically, the lever 158is designed as a two-legged right-angled deflection lever pivotallymounted in its central portion within the insertion mandrel 156, withone leg forming the actuation lever/actuating portion and the other legbeing operatively connected to the detent nose 160, which is preferablydesigned in the form of a push block and is urged radially outward bythe one leg of the actuation lever 158 via its spring bias.

FIG. 42 and FIG. 43 show the tool guiding device/saw block 8 with theinserted height adjustment unit 6 in different adjustment positions.

Between the adjustment position according to FIG. 42 and the adjustmentposition according to FIG. 43 , the adjusted cutting height/cuttingheight difference (also referred to as contact level) 366 can be seen.The contact level 368 defines the height of the contact tip 166 relativeto the horizontal saw slot in the saw block 8, which defines the cutlevel 370.

FIG. 44 again shows the tool guiding device 8 with the attached heightsensing element 152, which includes the spiral element/spindle 168. Inturn, the spiral element 168 is operable via the spiral wheel 172 toadjust the height of the height sensing assembly 152. Specifically, thespiral/spindle 168 is guided for relative rotation preferably in theinsertion mandrel 156, with the height sensing assembly 152 beingthreadedly mounted on the spiral element 168 via the frictional element354. The spiral wheel 172 is in turn (as a further component of theheight sensing assembly 152) mounted for relative rotation on thefrictional element 354, so that rotation of the spiral wheel 172 on thespiral/spindle 168 results in a displacement of the contact arm 338along the spindle 168. Finally, a latching mechanism 372 is preferablyarranged between the frictional element 354 and the spiral wheel 172,which is provided to maintain a defined height (axial position on thespindle) of the height adjustment element 152.

The mode of operation of the height adjustment unit/cutting heightfeeler 6 according to the present invention can be summarized asfollows:

The adjustable cutting height feeler 6 has the basic function of beingprovided as a simple assembly and disassembly unit on the tool guidingdevice 8, i.e. on the tibia saw block. Attached to the distal end of thestylus, i.e., the height arresting unit 6, is the spring-loaded latchingmechanism, which is denoted here throughout by reference sign 154. Thelatching mechanism 154 arrests the stylus after the latter has beenput/inserted into the seating recess (through hole) 150 of the tibia sawblock 8 provided for this purpose, while the stylus preferably remainsrotatable about the insertion axis.

The axial arresting is achieved via the spring-loaded detent nose 160.This means that during putting/inserting the insertion mandrel 156 intothe seating recess 150, the spring-loaded detent nose 160 is pushedlaterally back into the insertion mandrel 156 due to its outer beveled(distal) contact/sliding surface, and when fully inserted in the tibiasaw block 8, the detent nose 160 is preferably latched in place in agroove in the tibia saw block 8. From the latching position, thespring-loaded detent nose 160 is released by means of the actuationlever 158, which retracts the detent nose 160 against the spring 164when the actuation lever 158 is manually pivoted. In this state, thestylus can be easily removed from the saw block 8. The contact tip 166further causes a bony landmark of the tibia to be sensed. The landmarkselected by the user is the reference relative to which the cuttingheight of the tool guiding device 8 is adjusted by rotating the spiralwheel 172 accordingly. The landmark is detected by the contact tip 166,which is attached to the end of the contact arm 338. Due to the tactileaccuracy of the contact tip 166, even very small bony structures can bedetected visually very well and accurately by means of eye control.

The horizontal movability of the height sensing assembly 152, inparticular of the contact arm 338 is used for adaptation to thedifferent anatomies of the tibia and to achieve the medial and lateraltibial alignment from the same adapter location. For this purpose, thehorizontal movability of the contact arm 338 at the frictional element354 is provided, which is shown in FIG. 37 . With the help of therotating stylus and the contact arm 338, which can be moved along itsmain axis, any bony landmark on the proximal surface of the tibia can bereached. The dimensions of the contact arm 338 are designed in such away that the anatomy existing worldwide (e.g. of Asian or Caucasianpeople) can be taken into account.

In order to maintain the desired extended length of the contact arm 338,the contact arm 338 is secured in self-locking manner on the frictionalelement 354 by means of frictional engagement against displacement inaxial direction. Due to the fact that the stylus latches in place in thetool guiding device 8, i.e. in the tibia saw block, and a defined stopof the stylus on the saw block 8, the distance of the contact tip 166 ofthe stylus relative to the lower edge of the saw key in the saw block 8is safely achieved, the set cutting height being indicated, for example,by numbers 344 on the circumference of the spiral wheel 172. The numberindicating the set height is preferably indexed with a pointing elementat the anterior end of the frictional element 354 (holding unit).

For example, setting the tibia section thickness from 0 to 16 mm (orfrom 0 to 14 mm) is achieved with only one rotation of the spiral wheel172. A stop element/stop portion at the upper end of the spiral 168prevents the spiral wheel 172 from being completely unscrewed from thestylus.

After setting the desired cutting height relative to the contact tip166, the height sensing assembly 152 is moved against the landmarkselected by the user and the alignment device is aligned. The landmarkis approached in particular by (manually) moving the handle 14 with themounting elements along the slide rod 11 with the distal clamping device2 being already in engagement. Once the alignment device 1 is alignedwith regard to height, varus, valgus and slope as desired by the user,the tool guiding device 8, i.e. the saw block, is finally firmlyanchored to the bone with fixation pins, preferably nails, through thefixation holes 300 provided for this purpose. Afterwards, the stylusmust/can be removed in order to be able to perform the tibial saw cut.For this purpose, the telescopic device 1 can remain on the tibia orsimply be removed together with the clamping device 2 and the adapter12, whereas the saw block 8 (without the already removed contact device6) remains on the tibia.

In the following, a proximal fixation unit/fixation device 202 isdescribed, which can selectively be mounted on the proximal end portionof the telescopic device 10 preferably as described above, in order toconvert an alignment device of the anterior fixation version into analignment device of the proximal fixation version.

For this purpose, FIG. 45 shows an optional proximal drivedevice/fixation unit 202, preferably comprising at least the following:

-   a drive mechanism 224 designed to drive in preferably two pins    slidably guided in the drive mechanism 224,-   an impact lever 400 provided and designed for releasing the two pins    driven in, and-   a connecting mechanism 406 for a (preferably clamping) connection    between the proximal fixation unit 202 to the alignment device    (telescopic device) according to the version “anterior fixation” for    selectively/temporarily creating an alignment device in the version    “proximal fixation”.

Specifically, the fixation device 202 has a transverse beam 222 at onefree end portion of which the drive mechanism 224 and the impact lever400 are disposed. The drive mechanism 224 has a drive pin unit 404,which is used as a kind of anvil for the preferably two drive pins. Forthis purpose, a central guide pin 200 is (fixedly) anchored in thetransverse beam 222 at an angle close to 90° relative to the transversebeam’s longitudinal axis, on which the anvil is slidably mounted in theform of a frame/frame housing 201 surrounding the guide pin 200. On anunderside of the anvil/frame 201 facing the transverse beam 222, thepreferably two drive pins 203 are fixed in parallel alignment to theguide pin 200, which are preferably mounted/guided in two through holeson the transverse beam 222. If a hammer blow is thus manually applied tothe anvil, the pins 203, which are held/fixed thereto and guidedlongitudinally in the transverse beam 222, are driven into a patientbone, with the impact direction being ensured by the guide pin 200 whichis fixed to the transverse beam 222 and guides the anvil longitudinally.

The impact lever 400 is hinged to the transverse beam 222 in arocker-like manner and has an engagement portion on a side facing thedrive mechanism 224, which is in operative engagement with theanvil/frame housing 201, and an impact portion on an opposite side,which can be struck with a hammer or similar impact tool. That is, whenthe impact portion of the rocker-like impact lever 400 is struck, itsengaging portion exerts a force on the underside of the frame housing201 in opposition to the pin impact device, thereby pulling the pins 203out of the patient bone.

The transverse beam 222 is axially slidably inserted in an accommodationcase/fixation element 402, which accommodates a slip/sliding brake(indicated in FIG. 45 ) 405, for example in the form of a curved leafspring, that slows down an axial sliding movement of the transverse beam222 in the accommodation case 402. In this context, the transverse beam222 is preferably made of a polygonal profile (rectangular profile) sothat rotation of the transverse beam 222 about its longitudinal axis inthe case 402 can be prevented.

Fixed to the accommodation case 402 is a support column 408 which isaligned at a substantially right angle or slightly inclined to thetransverse beam 222 and in/on which the connecting mechanism 406 ispreferably provided in the form of a latching/clamping mechanism 208(see in particular FIG. 47 ) for selectively fastening the fixation unit202 to the telescopic device 10. According to FIG. 47 , this clampingmechanism 208 consists essentially of a wedge-shaped clamping plate 216that rests against the free distal end face of the support column 408,the end face of the support column 408 being preferably beveled/inclinedin a wedge shape with respect to the longitudinal axis of the column.The support column 408 is formed from an at least partially tubular(hollow) body 210, in which a tension element (tension rod) or controlelement 210 is mounted in longitudinally movable manner. The clampingplate 216 is operatively connected via the tension element (tension rod)or control element 210 guided in the support column 408 to an actuatinglever 214, which is pivotably mounted on the accommodation case 402 forthe transverse beam 222. According to FIGS. 48 and 49 , the actuatinglever 214 has an actuation portion with a preferably roughened or ribbedpushbutton for a nonslip pressurization of the actuating lever 214, forexample by means of a thumb of the user. Consequently, if the actuatinglever 214 is flipped and hence a tensile force applied to the tensionrod 210, the wedge-shaped clamping plate 216 is thereby displacedradially outwards along the (wedge-shaped) chamfered end face 218 of thesupport column 408, thereby artificially increasing the overallcross-sectional area of the column 408.

The support column 408 also has a region with a small cross-section(cross-sectional area) at its (distal) end portion facing away from thecase and a region with a large cross-section (cross-sectional area) inits (proximal) end portion facing the case, which are separated fromeach other by a circumferential shoulder (see in particular FIG. 48 ).The region with small cross-section is dimensioned such that it can beinserted (with slight play) into the hollow telescopic rod/slide rodelement 11 of the telescopic device 10 and arrested therein by means ofthe clamping mechanism 208. The region of large cross-sectioncorresponds substantially to the outer cross-section of the slide rodelement 11, so that when the support column 408 is fully inserted in theslide rod element 11 (up to the circumferential shoulder as a stop), asubstantially smooth slide rod surface is produced.

FIG. 46 shows the fixation unit 202 with the drive mechanism 224including their actuation options. Fixation is thus effected by drivingin the pins 203 preferably by a hammer blow. A further hammer blowagainst the impact lever 400 releases the pins 203. The clampingmechanism 208 is activated/deactivated by actuating the pushbutton 214.

FIG. 47 shows the fixation unit 202, which comprises the fixationmechanism 224 and the connection/clamping mechanism 208. If theconnection/clamping mechanism 208 or its manual actuation lever 214 isin the upwardly pulled position (toward proximal), the clamping actionbetween the support column 408 and the slide rod element 11, into whichthe support column 408 is inserted in the proximal fixation variant ofthe alignment device 1, is cancelled. Here, the connection/clampingmechanism 208 acts via the control element/pull rod 210 on thewedge-shaped clamping plate 216, which is movable radially outwards orinwards with respect to the support column 408 by the chamfer 218 of thedistal end face of the support column 408. As soon as the clamping plate216 is pulled upwards (toward proximal) via the pull rod 210 by pushingthe actuating lever 214 downwards (toward distal), the clamping plate216 is moved laterally, in particular radially outwards into a clampingposition with the slide rod 11, into which the support column 408 isalready inserted. If, on the other hand, the lever 214 is pressedupwards, the control element 210, i.e. the rod, moves downwards (towarddistal) and releases the clamping plate 216. The latter moves radiallyinwards as a result of its wedge shape, which removes the clampingeffect.

FIG. 47 shows an enlarged view of the closed clamping mechanism 208according to FIG. 48 , in which the actuating lever 216 has been moveddownward, as already described above. Accordingly, the wedge-shapedclamping plate 216 is also beveled at its side facing the support column408 at an angle of approximately 45° with respect to the central axis ofthe plate. An approximately equal bevel is also found on the free(distal) end face of the support column 408, so that in the event of anoperative/sliding engagement of both bevel sides, the clamping plate 216remains aligned approximately perpendicular to the central axis of thesupport column 408. However, as an alternative to this design, it isalso possible according to FIGS. 48 to 51 to provide a type of expandingcone at the distal end/end portion of the hollow support column 408 thatpulls the distal end portion into the hollow/tubular support column 408and elastically expands it radially if the actuating lever 214 isactuated accordingly. For this purpose, the support column 408 may beformed with expanding slots (not further shown) in its distal endportion. It is also conceivable to provide an elastic bracing body(e.g., made of a plastic material) at the distal end of the supportcolumn 408, which is axially compressed when the lever 214 is actuated,thereby displacing plastic material radially outward.

FIGS. 52 to 55 show the alignment device in the “anterior fixationvariant”, in particular its telescopic device 10 comprising the toolguiding device 8 already adapted to the telescopic device 10. Alongitudinal axis 20 extends in the longitudinal direction of thetelescopic device 10 as a reference axis, which also represents thecentral axis of the slide rod 11 according to FIG. 52 at the same time.The saw block adapter 12 is clearly visible, which is guided (along thelongitudinal axis 20) so as to be axially movable over the slide rod 11by means of the adapter above/proximal to the handle 14, with the sliderod 11 protruding at the top side (proximal side) of the saw blockadapter 12 from the through opening formed therein and accommodating theslide rod 11, as shown for example in FIG. 54 .

FIG. 53 shows the telescopic device 10 in exploded view, according towhich the slide rod 11 is designed as a hollow shaft that has an openend face toward proximal. The illustrated exploded view shows the toolguiding device / saw block 8 and the optional fixation unit 202 forselectively establishing the alignment device 1 as a “proximal fixationvariant”. The outer dimensions of the slide rod 11 as well as of thesupport column 408 of the fixation unit 202 are clearly illustrated, insuch a way that the support column 408 can be inserted in its distal endportion with a small outer diameter almost without play into the sliderod 11 not more than up to the shoulder for a lengthadjustment/adaptation of the slide rod 11 to the patient’s anatomy,which separates the support column’s own distal end portion with smallouter diameter from the proximal portion with large outer diameter,which essentially corresponds to the outer diameter of the slide rod 11.

FIG. 54 shows the tool guiding device 8 and the adapter 12 placed on theslide rod 11 above the handle 14, the actuating element of which,preferably the push/pushbutton 410, being not actuated/depressed so thatthe tibia cut block adapter 12 is arrested on the handle 14 of thetelescopic device 10 to form a unit. In this state, the handle 14 can beshifted relative to the slide rod 11 for alignment of the contact needle166. This corresponds to an alignment device 1 of the anterior fixationvariant. In contrast, FIG. 55 shows the telescopic device 10 in whichthe pushbutton 410 on the adapter 12 has been pressed and thus the tibiacut block adapter 12 is released from the handle 14 and thus freelymovable relative to it. The drive device 202 is inserted into the hollowbody/slide rod element 11. This corresponds to the alignment device 1 inthe proximal fixation variant, according to which the telescopic device10, i.e. the slide rod 11, is extended by the support column 408 towardproximal, thus forming an extended movement guide for the saw blockadapter 12.

FIG. 56 shows at set 250 of slide rod elements, for example comprisingat least two slide rod elements 254 and 258 of differing lengths. By wayof example, the first slide rod element 254 has a first (short) length,which is for example 207 mm, which thus characterizes the short sliderod. The second slide rod 258 has a second (long) length that isdifferent from the first length and is, for example, 264 mm. Thelongitudinal axis of the foot clamp reception device/ reception duct 5defines the respective lower point of the slide rods 254, 258, fromwhich the slide rod length can be measured in each case.

It should be noted at this point that the set 250 of slide rodsaccording to the invention can also have more than two slide rods ofdiffering lengths. As an alternative or in addition to this, it is alsoperfectly conceivable to provide several fixation units with supportcolumns 408 of differing lengths in one set for this purpose, in orderto take different patient anatomies into account.

FIG. 57 shows the distal end region of the telescopic device 10 with thefoot clamp reception device/ reception duct 5, which is attached to thefirst (short) slide rod 254. The cantilever arm 93 is received here bythe foot clamp reception device 5. The clamping elements 4, 4 a arearranged to be offset with respect to the cantilever arm 93 by acorresponding rotational orientation of the cantilever arm 93 in thereception duct 5 towards the distal end. This results in a change inlength of +15 mm compared to a central clamping element arrangement, asalready explained above.

FIG. 58 shows a second position of the foot clamp device. In this case,the clamping elements 4, 4 a are offset towards the proximal end (i.e.upwards) with respect to the cantilever arm 93, as a result of which thecantilever arm 93 is in turn accommodated by the foot clamp receptiondevice 5. The central axis of the foot clamp reception devices 2 and theupper edge of the foot clamp elements 4, 4 a show the height offset 268.In the second position, an average change in length of -15 mm isprovided compared to a central clamping element arrangement.

FIG. 59 shows the alignment device 1 with the tool guiding device 8,which is placed on the short slide rod 254. FIG. 60 shows the alignmentdevice 1 with the long slide rod 258, which protrudes significantlyfurther beyond the handle 14 toward proximal than the short slide rodversion.

FIG. 61 shows the alignment device 1 with the tool guiding device 8 andthe contact device 6 for the version “anterior fixation”, in which thesaw block adapter 12 is detached from the handle 14 for fine adjustmentof the height distance between the contact needle 166 and the saw block8. FIG. 62 shows the alignment device 1, which comprises the toolguiding device 8 and on which the contact device 6 with the drive device202 for proximal fixation is additionally placed. Also in this case, thesaw block adapter 12 is detached from the handle 14. By forming the setof slide rods of different lengths according to the invention, thealignment device 1 is applicable for the different leg lengths givenworldwide, e.g. for Asians with short leg lengths or Caucasians withvery long leg lengths. This is advantageously achieved by simplyexchanging the slide rods with different rod lengths.

These length versions allow the following leg lengths to be adjusted:

-   The short slide rod 254 allows to adjust leg lengths of approx. 200    mm to approx. 380 mm, and-   The long slide rod 258 allows to adjust leg lengths from approx. 260    mm to approx. 438 mm.

Due to the overlap of the useful lengths of the two slide rod lengths254 and 258 of about 120 mm, the user can opt for one of the slide rods254, 258 and advantageously apply the alignment device 1 to a majorityof patients.

With respect to the two embodiments for alignment, the length settingspreferably differentiate as follows:

-   For example, for the “anterior fixation” shown in FIG. 61 , the    first slide rod 254 has a length 256 from about 200 mm to about 360    mm and the second slide rod element 258 has a length from about 260    mm to about 420 mm.-   For the alignment device 1 of the embodiment “proximal fixation”    shown in FIG. 62 , the first slide rod 254 of the short slide rod    length has a first length from 255 mm to about 380 mm. With respect    to the second length of the second slide rod element 258, the second    slide rod element, for the embodiment of proximal fixation shown in    FIG. 62 , has a length from about 315 mm to about 438 mm.

Furthermore, a change in length of + or -15 mm is achieved by theability of turning the foot clamp 2 by 180°, as shown in FIGS. 57 and 58according to the above description. This change in length isadvantageously achieved without the need to replace the slide rod 11.The described change in length of + or -15 mm, which is achieved by theability of turning the foot clamp, is already included in the abovedescription of the change in length of the alignment device. For veryshort lengths of the tibia, it is still possible to reduce theadjustment to approx. 180 mm with the “anterior fixation”, as shown inFIG. 61 . However, this has the consequence that the oblong hole ordrive slot 302 in the tool guiding device 8, i.e. in the tibia sawblock, cannot be used for the primary anterior fixation version of thealignment device (the ETA).

Preferred embodiments of the alignment device 1 according to theinvention are summarized below:

A first embodiment of the alignment device 1 for a tibial resectionguide comprises:

-   a clamping device 2 having at least two clamping elements 4, 4 a    acting against one another for clamping the distal end of a tibia 3    of a patient;-   a tool guiding device or saw block 8 for guiding a tool during the    resection of the tibia 3,-   optionally, a contact device 6 for contacting the proximal end of    the tibia 3, mountable to the tool guiding device 8; and-   a telescopic device 10 which is proximally connected to the tool    guiding device 8 and distally connected to the clamping device 2 in    separable manner and designed to align the devices 2, 6 with respect    to the tibia 3, wherein-   the telescopic device 10 additionally comprises in its proximal    region 52 a decoupling device or cut block adapter 12 designed to    separate the saw block 8 from the telescopic device 10 upon manual    activation; and/or that-   the clamping elements 4 of the clamping device 2 are flexurally    elastic so that the telescopic device 10 can be removed from the    tibia preferably after activation of the decoupling device 12 by    utilizing the flexural elasticity of the clamping elements.

Further, it may be provided that the telescopic device 10 has a handle14 in its proximal region 52, which handle is designed in such a waythat it can be grasped by the one hand of an operator, and that thedecoupling device/saw block adapter 12, above the handle 14, has anactuation/pressure element 16 for activation/saw block release, which ispreferably arranged at an angle A 18 between 90° and 150°, morepreferably at an angle A between 95° and 120° degrees and in particularat an angle A 18 of 100° to the longitudinal axis 20 of the telescopicdevice 10, so that the pressure element 16 can be actuated by the thumbof the one hand 56.

It may further be provided that the clamping device 2 is arranged in thedistal region 54 of the telescopic device and that the two resilientclamping elements 4, 4 a each have an arcuate shape which are alignedwith respect to each other such that, when viewed in the direction ofthe longitudinal axis 20 of the telescopic device 10, they form betweenthem, in the closed state, an oval-shaped region 22 which is providedfor receiving the distal region of the tibia 3 in a clamping manner.

Further, it may be provided that the decoupling device 12 has a basebody 24 comprising at least one male (or female) receiving element 26designed to come into form-fitting engagement with at least one female(or male) receiving element 28 of the tool guiding device 8 and that theactuating/pressure element 16 of the decoupling device 12 has anoperatively connected hook/bracket element 30 designed to comprise anundercut on the tool guiding device 8, preferably at least one pinelement 44 extending from the tool guiding device 8 in transversedirection 32 to the longitudinal axis 34, so that in the closed state adisengagement of the receiving elements 26, 28 from each other isprevented. In a preferred manner, the male receiving elements 28 areconeshaped.

Further, it may be provided that the base body 24 of the decouplingdevice 12 comprises a bearing journal which, viewed in transversedirection, is arranged preferably between the at least one malereceiving element 26 and a seating recess 40 for a slide rod 11 of thetelescopic device 10, and that the hook/bracket element 30 is pivotallyarranged/mounted on the bearing journal, preferably at an angle of up to30°.

Further, it may be provided that the pin element 44 of the tool guidingdevice 8 is of drop-shaped design when viewed in transverse directionand that, when the male receiving element 26 of the tool guiding device8 is mated with the female receiving element 28 of the base body 24, thehook element 30 slides along the drop shape 44 and is thereby lifted sothat the hook element 30 gets latched with the drop-shaped pin element44 when the receiving elements 26, 28 are mated.

Further, it may be provided that the base body 24 of the decouplingdevice additionally comprises a stop pin extending in its transversedirection 32, which is preferably arranged between the bearing pin and astop surface for the tool guiding device 8, and that a stop notch isadditionally formed in the hook element 30, which is provided to formthe pivot end stop of the hook element 30 by cooperating with the stoppin when the tool guiding device 8 is not latched in place.

An embodiment of the alignment device 1 for a tibial resection guide isprovided in that its distal region 54 has a clamping device 2 comprisingat least two clamping elements 4, 4 a acting against one another forclamping the distal end of a tibia of a patient; the clamping elements 4of the clamping device 2 being each of arcuate design and aligned withrespect to each other so as to form an oval-shaped region 22 betweenthem (in a closed state), as viewed in the direction of the longitudinalaxis 20 of the alignment device 1, said oval-shaped region beingdesigned for receiving the distal region of the tibia in a clampingmanner, the clamping elements 4, 4 a being each of resilient design sothat the clamping device 2 of the alignment device (1) can be removedfrom the tibia (5) with one hand.

Further, it may be provided that the clamping elements 4, 4 a areadditionally designed so as to be fork-shaped and that the prongs 62 ofthe respective fork 60 are arranged in offset manner relative to oneanother such that in the closed state they engage into one another in anoverlapping manner so that the tibia 3 is held in place.

Further, it may be provided that the respective tips 66 of the prongs 62are shaped in opposite direction with regard to the respective arcuateshape of the clamping elements 4,4a so that the removal process from thetibia 3 is atraumatic.

Further, it may be provided that the (distal/close-to-hinge) ends 68 ofthe clamping elements/clamping forks 4, 4 a are each enclosed/embracedand retained by a reinforcing element 70, which connects the respectiveclamping element 4, 4 a to a respective latching element 74 bonded to aV-shaped contact block 86, the reinforcing element 70 being preferablymade of plastics.

It may further be provided that the latching elements 74 each comprise aratchet mechanism 76 so that the clamping elements/clamping forks 4, 4 acan be pretensioned such that an adjustable pretensioning force acts onthe tibia in the closed state 64.

Further, it may be provided that the V-shaped contact block 86, viewedin the longitudinal direction 20 of the alignment device 1, has acentral contact area 78, from which lateral contact arms 82 each extendin a V-shape on both sides, with an angle C preferably in a regionbetween 30° and 60°, more preferably in a region between 40° and 50° andin particular with an angle of 45°.

Further, it may be provided that the V-shaped bearing block 86 iscoupled to a T-piece 92 via a spindle mechanism 90 in a laterallyadjustable manner (resulting in an overall Y-shape in interaction withthe bearing arms 82 of the bearing block 86), which is preferablyadjustably connected to the telescopic device 10 of the alignment device1 via a latching structure 94.

An embodiment of the alignment device 1 for a tibial resection guidecomprises

-   a (distal) clamping device 2 for clamping the distal end of a tibia    of a patient;-   a (proximal) tool guiding device 8 for guiding a tool during the    resection of the tibia,-   a telescopic device 10 which is proximally connected/connectable to    the tool guiding device 8 and distally connected/connectable to the    clamping device 2 and designed to align the proximal and distal    devices 2, 6 with respect to the tibia, the telescopic device 10    having a handle element 14 designed to receive, in extendable    manner, a slide rod element 11 slidably mounted therein, wherein    -   the telescopic device 10 comprises an arresting/securing element        104, which is arranged between the handle element 14 and the        slide rod element 11 and which can be adjusted to reach a first        position in which a first compressive force is effected between        the elements 14, 11, which allows a braked relative displacement        of both elements 14, 11, and which can additionally be adjusted        to reach a second position in which a second compressive force        is effected between the elements 14, 11, which arrests both        elements 14, 11 relative to each other.

Further, it may be provided that the securing element 104 isadditionally adjustable such that in a third position a thirdcompressive force acts between the elements 14, 11 which allows asubstantially unbraked relative displacement of both elements 14, 11.

It may further be provided that a locking element 112 is arrangedbetween the securing element 104 and the telescopic device 10, which isdesigned to hold the securing element 104 on the telescopic device 10 ina locking position and to cause a release of the securing element 104 ina release position, so that the latter is removable from the telescopicdevice 10.

Further, it may be provided that the slide rod element 11 has agroove-shaped recess 118 in its longitudinal extension, which isprovided to receive a clamping pin 120 of the securing element 104 andto guide it. The groove-shaped recess 118 advantageously provides adefined guidance of the clamping pin 120.

Further, it may be provided that the securing element 104 comprises anadjusting element 122 which acts on a spring element 124 of the securingelement 104 in such a way that the pressure/clamping forces generated bythe spring element 124 are adjustable in the respective positions 106,108, 110.

Further, it may be provided that, when viewed in the transversedirection 32 of the alignment device 1, a receiving element/receivingportion 100 is arranged/formed on the handle 14 on the far side of thetibia, which is designed to receive the locking element 112 preferablyin a movable manner.

Further, it may be provided that the slide rod element 11 has stops 128,130 for the securing element 104 in its groove-shaped recess 118 at itstwo axial end portions in order to prevent the slide rod element 11 fromsliding out of the handle element 14.

An embodiment of the alignment device 1 for a tibial resection guidecomprises

-   a clamping device 2 for clamping the distal end of a tibia 3 of a    patient;-   a tool guiding device 8 for guiding a tool during the resection of    the tibia,-   a telescopic device 10 proximally connected to the tool guiding    device 8 and distally connected to the clamping device 2 and    designed to align the devices 2, 8 with respect to the tibia 3,    wherein    -   the tool guiding device 8 has a seating recess 150 which is        designed to receive, in a releasable manner, a contact device 6        for sensing the resection height.

Further, it may be provided that the seating recess 150 is a boreextending from the proximal top side 151 of the tool guiding device 8along the longitudinal axis 20 of the alignment device 1 and that thecontact device 6 comprises an insertion element/insertion mandrel 156having a latching mechanism 154, which insertion element/insertionmandrel can be (axially) latched (and rotatably) inserted in the seatingrecess 150.

It may further be provided that the latching mechanism 154 has a leverelement/an actuating lever 158, which is preferably arranged in/on theinsertion mandrel 156 and via which a detent nose 160 can be actuated,which in the inserted state of the insertion mandrel 156 engages behindthe seating recess 150 in order to hold the contact device 6 axiallytherein.

It may further be provided that the contact device 6 comprises a heightsensing assembly 152 having a contact tip 166 arranged at the proximalend of a contact arm 338, which contact tip may be adjustably arrestedon the tool guiding device 8 in longitudinal direction 34 and intransverse direction 32 of the alignment device 1.

Further, it may be provided that a spiral element 168 is providedbetween the insertion mandrel 156 and the contact tip 166 for adjustmentin longitudinal direction 20, which preferably slidably/freelypenetrates the contact arm 338 and is designed to readably output theheight distance of the contact tip 166 relative to a cutting plane 170of the tool guiding device 8.

Further, it may be provided that the spiral element 168 has a spiralwheel 172 which is held relatively rotatably thereon and is in screwengagement with the spiral element 168, which is preferably providedwith numerical values 174 on its circumferential side and via which theheight distance can be adjusted.

An embodiment of the alignment device 1 for a tibial resection guidecomprises:

-   a (distal) clamping device 2 for clamping the distal end of a tibia    3 of a patient;-   a (proximal) tool guiding device 8 for guiding a tool during the    resection of the tibia,-   a telescopic device 10 with a handle 14 and a slide rod 11 slidably    guided in the handle 14, the telescopic device 10 being proximally    connected to the tool guiding device 8 and distally connected to the    clamping device 2 and designed to align the devices 2, 8    (longitudinally) with respect to the tibia 3, wherein    -   the telescopic device 10 comprises, in its proximal end region        52, a drive device mount 204 for receiving a drive device 202,        which is formed by the slide rod 11 of the telescopic device 10        designed at least in sections as a hollow body. Preferably, the        slide rod 11 completely penetrates the handle 14 in the        longitudinal direction of the telescopic device 10 (in the        design position) and thus forms the drive device mount 204        proximally to the handle 14.

Further, it may be provided that the drive device 202 can be inserted atits distal end into the hollow body portion of the slide rod 11 in sucha way that a clamping of the drive device 202 in the hollow body sectioncan be effected via a clamping mechanism 208 on the side of the drivedevice 202.

Further, it may be provided that the clamping mechanism 208 comprises anelongated control element 210 preferably in the form of atension/compression rod, which is movably guided within a hollowbody/support tube 408 of the drive device 202 and which is movable atits proximal region via a lever element 214 in longitudinal direction 20in such a way that a (manual) actuating force acting on the leverelement 214 can be effected on a clamping/cant element 216 clampablewith the hollow body portion of the slide rod 11.

Further, it may be provided that the hollow body 408 of the drive device202 has a chamfer 218 in its distal end/end face and that the cantelement 216 also has a corresponding chamfer 220 at its end/end facefacing the control element 210, so that the cant element 216 slides offon the hollow body 408 of the drive device 202 in the transverse/radialdirection 32 when a tensile force is applied by the control element 210,so that the cant element 216 of the drive device 202 can be clamped tothe slide rod 11 of the telescopic device 10.

Further, it may be provided that the drive device 202 in the insertedstate is circumferentially flush with the slide rod 11 of the telescopicdevice 10 such that the tool guiding device 8 is movable in thelongitudinal direction 20 along the slide rod 11 of the telescopicdevice 10 and along the hollow body 408 of the drive device 202.

Further, it may be provided that the drive device 202 comprises at itsproximal end portion a transverse beam 222 which is longitudinallyslidably mounted on the hollow body 408 of the drive device 202substantially perpendicular to the hollow body 408 and which comprisesat its free (proximal) end portion a fixation device 224 for proximalfixation of the alignment device 1 to the tibia 3. In an advantageousmanner, the drive device 202 is supported to be freely movable in allthree spatial directions (i.e. in the height direction along the hollowbody 408, in the transverse direction along the transverse beam 222 and,if necessary, rotationally around the hollow body 408) by thisembodiment and can thus be adapted to the respective boundaryconditions.

A preferred embodiment of the alignment device 1 comprises:

-   a (distal) clamping device 2 comprising at least two mutually    pivotable clamping elements/clamping arms 4, 4 a for clamping the    distal end of a tibia 3 of a patient, which are mounted on a    cantilever arm 93 designed to be inserted into a (distal) foot clamp    reception device 5 on a telescopic device 10 of the alignment device    1,-   a tool guiding device 8 for guiding a tool during the resection of    the tibia,-   the telescopic device 10, which is connected to the tool guiding    device 8 and to the clamping device 2 and which is designed to align    the devices 2, 6 with respect to the tibia 3, the telescopic device    10 comprising a handle element 14 which supports a slide rod element    11 so as to be longitudinally movable therein, wherein    -   the alignment device 1 comprises a set 250 of slide rod        elements, having at least a first slide rod element 254 with a        first, short slide rod length and at least a second slide rod        element 258 with a second, long slide rod length, the respective        slide rod elements 254, 258 of the slide rod set 250 according        to the invention being provided to be inserted into the handle        element 14 as required, the respective slide rods 254, 258 of        the slide rod set 250 in other respects being designed to be        structurally identical to one another and in particular at their        distal end portions being connected to/formed with a foot clamp        reception device 5, and in that the ratio of the first length of        the first slide rod element 254 to the second length of the        second slide rod element 258 is preferably between 1 and 1.5,        more preferably between 1.1 and 1.3 and in particular amounts to        1.27, so that different lengths of the tibia can be resected by        the first and the second slide rod 254, 258 of the slide rod set        250, the length being measured from the proximal end of the        slide rod 254, 258 up to the central axis 262 of the foot clamp        reception device 5.

An embodiment of the alignment device 1 according to the inventionprovides that the clamping elements/clamping arms 4, 4 a of the footclamp reception device 5 are arranged to be axially offset with respectto the longitudinal direction of the cantilever arm 93, the cantileverarm 93 being insertable into the foot clamp reception device 5 by arespective rotation of 180° degrees in a first position and in a secondposition, so that in the first position the clamping elements 4, 4 a arepositioned toward the distal end of the alignment device 1 and in thesecond position toward the proximal end of the alignment device 1, as aresult of which a height/length offset of the clamping elements 4, 4 ain the longitudinal direction 20 of the telescopic device 10 is effectedif the cantilever arm 93 is inserted into the foot clamp receptiondevice 5 rotated by 180° degrees from the first to the second position.

Further, it may be provided that the height offset of the foot clampreception device 5 is measured from the central axis 262 of the footclamp reception device 5 to the respective articulation point 270 of theclamping elements 4, 4 a and is preferably between 10 mm and 20 mm andin particular is equal to 15 mm.

1. An alignment device comprising; a telescopic device configured to beequipped with a saw block at a proximal end portion of the telescopicdevice; and an ankle shackle device, that forms a clamping device at adistal end portion of the telescopic device, the clamping devicecomprising at least two clamping elements that are pivotable andconfigured to act against one another for clamping a distal end of, atibia of a patient, the clamping elements each being of arcuate design,and each of the clamping elements being resilient at least in sections,such that the clamping device is removable from the tibia of the patientexclusively by utilizing a spring elasticity of the clamping elements.2. The alignment device according to claim 1, wherein the clampingdevice comprises a tibia contact block having two contact arms that aresubstantially V-shaped, rigid and diverging, the clamping elements beingpivotally articulated to free end regions of the contact arms.
 3. Thealignment device according to claim 2, further comprising a ratchetmechanism via which the clamping elements are supported on the tibiacontact block and by which the clamping elements are configured to bepretensioned independently of each other.
 4. The alignment deviceaccording to claim 1, wherein the clamping elements are each fork-shapedwith prongs arranged in an offset manner relative to one another suchthat in the closed state the prongs mesh with one another in anoverlapping manner.
 5. An alignment device comprising a telescopicdevice configured to be equipped with a saw block at a proximal endregion of the telescopic device, the telescopic device comprising anankle shackle device at a distal end region of the telescopic device,the ankle shackle device being formed as a clamping device, thetelescopic device further comprising a saw block adapter in a proximalregion of the telescopic device, the saw block adapter configured toseparate the saw block from the telescopic device during a manualactivation.
 6. The alignment device according to claim 5, wherein thetelescopic device comprises a handle in the proximal region, said handleconfigured to be embraced with one hand, and wherein the saw blockadapter comprises a pressure element above the handle for activation,the pressure element being arranged at an angle A of between 90° and150°, relative to a longitudinal axis of the telescopic device so thatthe pressure element is in a position to be activated by said one hand.7. The alignment device according to claim 6, wherein: the saw blockadapter comprises a plug on which a clamp or bracket is supported on arocker, said clamp or bracket forms at least one engagement undercut ata first end portion of the clamp or bracket facing the saw block, andthe pressure element is configured for manually pivoting the clamp orbracket in a release direction, the pressure element being arranged on asecond end portion of the clamp or bracket.
 8. The alignment deviceaccording to claim 7, wherein: the saw block comprises a plug connectorthat is selectively engageable with the plug in a torque-proof manner,and engagement between the plug connector and the plug is secured by theretaining bracket by engaging behind holding edges on a side of the sawblock.
 9. The alignment device according to claim 6, wherein the sawblock adapter is formed as a separate part having a manually detachabledocking point at which the saw block adapter is connectable to thehandle, the saw block adapter comprising a through-hole such that thesaw block adapter is held on the telescopic device penetrating thethrough-hole and so as to be movable in a longitudinal direction of thethrough-hole.
 10. An alignment device comprising: a telescopic deviceconfigured to be equipped with a saw block at a proximal end portion ofthe telescopic device; and an ankle shackle device, that forms aclamping device at a distal end portion of the telescopic device, thetelescopic device having a handle and a slide rod element supported inthe handle so as to be longitudinally movable in the handle, thetelescopic device comprising a securing element that is manuallyadjustable and arranged on the handle, the securing element configuredto selectively produce a frictional force between the handle and theslide rod element, the securing element being adjustable to reach afirst position in which a first compressive force between the handle andthe slide rod element brought about, and the securing element beingadjustable to reach a second position in which a second compressiveforce, differing from the first compressive force, is brought aboutbetween the handle and the slide rod element.
 11. The alignment deviceaccording to claim 10, wherein the securing element has a housingconfigured to be inserted or screwed into the handle, a rotary knobbeing inserted or screwed into the housing and supporting a clamping pinin an axially movable manner which axially protrudes from the housing,the clamping pin being pretensioned in a protrusion direction within therotary knob by a spring, the spring being axially supported on therotary knob at an adjusting screw axially screwed into the rotary knob,the clamping pin having an axial portion which is surrounded by thespring and configured to be axially supported on the rotary knob on theadjusting screw when the rotary knob is inserted or screwed into thehousing to a predetermined depth.
 12. The alignment device according toclaim 11, wherein the clamping pin has an axial middle portion providedwith a circumferential collar that is ring-shaped, the circumferentialcollar being configured to act as a spring seat for the spring and as anaxial stop for the rotary knob for limiting an extent to which theclamping pin protrudes from the housing, the adjusting screw configuredto adjust a pretension of the spring in a position in which thecircumferential collar strikes the rotary knob.
 13. An alignment devicecomprising: an ankle shackle device that forms a clamping device; a sawblock for guiding a tool; a telescopic device that is proximallyconnectable to the saw block and distally connectable to the ankleshackle device; and a contact device for sensing a resection height fora tibia resection, the saw block comprising at least one seating recessadapted to receive the contact device in a detachable manner.
 14. Thealignment device according to claim 13, wherein the contact devicecomprises an insertion element having a springloaded latching mechanismthat is insertable into the at least one seating recess in a latchingmanner, such that the contact device is rotatable in an axially securedmanner, but is rotatable within the seating recess.
 15. An alignmentdevice comprising: an ankle shackle device that forms a clamping device;a saw block for guiding a tool; a telescopic device that is connectableto the saw block at a proximal end portion of the telescopic device andconnectable to the ankle shackle device at a distal end portion of thetelescopic device; and a proximal fixation unit, the telescopic devicecomprising a proximal region and a drive device mount in the proximalregion, the drive device mount configured for selectively receiving theproximal fixation unit and being formed by a slide rod element of thetelescopic device formed at least in parts as a hollow body.
 16. Thealignment device according to claim 15, wherein the proximal fixationunit comprises a horizontal cantilever arm or transverse beam having apin drive mechanism and a vertical support column having an integratedmechanism for clamping the proximal fixation unit on the alignmentdevice.
 17. An alignment device comprising: an ankle shackle device thatforms a clamping device; a saw block for guiding a tool; a telescopicdevice comprising a handle which is connectable to the saw block; aslide shaft element which is received in the handle in a movable mannerand is connectable to the ankle shackle device; and a plurality of slideshaft elements of differing shaft length, which are selectivelyinterchangeable and selectively insertable into the handle in atelescopic manner.
 18. An alignment device comprising: an ankle shackledevice formed as a clamping device; a saw block for guiding a tool; anda telescopic device comprising a handle connectable to the saw block anda slide shaft element which is movably received in the handle andconnectable to the ankle shackle device, the ankle shackle devicecomprising a coupling portion that forms an insertion rod that isinsertable into a seating on a side of the slide shaft element, as wellas an ankle shackle portion that forms two clamping elements pivotallysupported on a tibia contact block, the ankle shackle portion beingoffset with respect to the coupling portion in a longitudinal directionof the telescopic device.
 19. The alignment device according to claim18, wherein the coupling portion is configured for coupling to the slideshaft element in a first rotary position and a second rotary positionoffset from the first rotary position by 180°, wherein the ankle shackleportion comes to rest in the first rotary position proximally to thecoupling portion and comes to rest in the second rotary positiondistally to the coupling portion.